Fan Speed Control Strategies for CPU Cooling and Case Ventilation
Key Takeaways
-
Cooling fans are a vital part of computer hardware, as they cool the CPU and ventilate casing.
-
DC fans are supplied with DC power from regulated DC supply or motherboard header pins. These fans are also called 3-pin fans, as they come with 3 pins: a supply pin (usually 12 V DC), a ground pin, and a signal pin.
-
PWM fans are DC fans with an extra wire for PWM. PWM fans are 4-pin fans, where the fourth wire sends a PWM signal to the fan motor. The PWM signal is the control input of the PWM fan.
A cooling pad for laptop
Cooling fans are a vital part of computer hardware, as they cool the CPU and ventilate casing, enabling active cooling in computers. All computers have built-in fans, as they are one of the approved cooling mechanisms for processors. The fans in computers gather cool air from the ambient and expel the warm air outside. They also aid the working of heat sinks by distributing air across them. Here, we discuss two types of cooling fans—Pulse Width Modulated (PWM) fans and DC fans.
DC fan
When you are working on a laptop, you might observe variations in the heat produced. This variation in heat dissipation often leads to questions on cooling fans and their speed. When the laptop’s heat is less, there is not much need to run the fan at full speed. However, if the laptop is extremely hot, the computer might even need additional fans. The speed control of cooling fans is a much-debated topic and PWM fans and DC fans are the most frequently discussed solutions.
DC Fans or 3-Pin Fans
Generally, DC fans are used as chassis fans with low power consumption. They are supplied with DC power. These fans are also called 3-pin fans, as they come with 3 pins. The 3 pins are the supply pin (usually 12 V DC), ground pin, and a signal pin. In DC fans, the power supply can be from a regulated DC source or from the motherboard header pins. The signal pin collects the information about the rotation speed of the fan (tachometer output) even when there is no speed control implemented. Some computers monitor the signal pin and signal an alert when the fan operation fails.
PWM fan
If you want to vary the speed of DC fans, the only option is to vary the input DC supply. The DC power supply can be reduced below 12 V for lower speeds. There are still limitations in the percentage decrease in the speed of DC fans. All the DC fans are specified with a minimum threshold voltage rating; if the voltage falls below the threshold, the fan starts to stall. For continuous spinning motion, this minimum voltage needs to be supplied.
DC voltage control is the method to vary DC fan speed and this can be implemented by incorporating resistances in the supply wire. The voltage drop across the series resistor reduces the voltage reaching the fan supply pin, automatically slowing the speed of the fan. If the resistor connected is a variable one, the fan speed can be varied until it stalls at a minimum threshold voltage. Nowadays, standalone fan controllers with knobs are available for this type of DC fan speed control.
PWM Fans or 4-Pin Fans
Pulse width modulation (PWM) fans are DC fans with an extra wire for PWM. PWM fans are 4-pin fans where the fourth wire sends a PWM signal to the fan motor. The PWM signal is the control input of the PWM fan. The control input is usually an open-drain or open-collector output with a 5 V or 3.3 V pull-up. The PWM control signals are square waves of high frequency, usually 25kHz or above, to make the noise from the fan above the audible human range. The PWM signal can start or stop the motor, depending on the high and low state of it. When the PWM signal is high, the motor runs, otherwise, the motor is stationary.
The duty cycle of the PWM signal controls the speed of the fan motor. The motor will be supplied with 12 V throughout, however, the duty cycle of the PWM signal decides how long the fan should be running or not. A duty cycle of 40% keeps the fan on for 40% of the total time period of the PWM signal, and the other 60% of the time it will remain off. The speed variation of cooling fans is within 30-100% of the rated speed, with the PWM technique and the minimum speed achieved by PWM fans being much lower than DC fans. The chassis and CPU temperature are the two factors that influence the speed of the cooling fans. The new technology advancements have brought firmware and software controlled PWM fans, where the speed is controlled according to the CPU or case temperature. The PWM fans are commonly seen as CPU coolers with higher power consumption.
DC Fan |
PWM Fan |
3-pin fan |
4-pin fan |
Voltage control |
PWM control |
The supply voltage is varied for speed control |
The supply voltage is constant throughout the operation, the PWM signal duty cycle controls fan speed |
Precise speed control is difficult |
Seamless speed control |
Limited in reducing speed below that which corresponds to the minimum threshold voltage |
The minimum speed achieved can be below DC fans |
Speed can be lowered up to 40% of the rated speed |
The lowest speed can be less than 20% of the rated speed |
Possibility of motor stalling below the minimum threshold voltage |
No chance of motor stalling |
Commonly used as chassis fans with low power consumption |
Commonly used as a CPU cooler with higher power consumption |
Comparison between DC fans and PWM fans
If you want to implement PWM fans or DC fans to control the speed of your computer’s cooling fan, the PCB Design and Analysis tools from Cadence can help. OrCAD software from Cadence can give you a wider outlook on DC voltage control or duty cycle control. If you’re looking to learn more about how Cadence has the solution for you, talk to us and our team of experts. To watch videos about related topics or see what’s new with our suite of design and analysis tools, subscribe to our YouTube channel.
Cadence PCB solutions is a complete front to back design tool to enable fast and efficient product creation. Cadence enables users accurately shorten design cycles to hand off to manufacturing through modern, IPC-2581 industry standard.
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Which Is Better to Cool Your PC?
Computers generate a lot of heat, but excessive heat can cause damage to the internal components of your PC. Fans are a vital part of your PC that helps minimize this heat and keep your computer running stable.
If you’ve ever built a PC or dug into your BIOS, you might’ve come across the terms DC and PWM — the two primary types of fans in a computer. So, what are they? Here, we’ll look at the differences and determine which fan is better for your needs.
What are DC and PWM Fans?
Direct Current (DC) and Pulse Width Modulation (PWM) fans are the two main types found in computers. These fans differ in crucial ways that change how you use them in a computer.
What’s a DC Fan?
A DC fan is a traditional computer fan. They run on a fixed voltage from a DC power supply or via the motherboard and provide consistent cooling to your computer.
DC fans have 3-pin connectors: A power supply pin, a ground pin, and a signal pin. The signal pin collects information about how fast the fan is spinning (called tachometer output) and alerts if the fan stops working.
The most common voltage for DC fans is 12V, though they also come in 5V, 24V, and 48V. The higher the voltage, the quicker the fan speed, and the greater the cooling. This means that you can lower the fan speed by reducing the voltage, though most fans will stall below a certain speed.
Some DC fans now come with a voltage controller built-in, though it’s also possible to alter the voltage through the BIOS or with a third-party fan controller.
Read More: The Best PC Fan Controllers
What’s a PWM Fan?
PWM fans are very similar to DC fans but differ in one key aspect: They have an extra pin for pulse width modulation. This fourth pin takes input from the motherboard to directly control the fan’s speed.
PWM fans work via repeated pulses of power. Essentially, PWM fans are either ON or OFF and can be switched from one to the other rapidly to control the overall fan speed. This pulsing is called a duty cycle. A 40% duty cycle, for example, means that for one entire cycle, the fan is only running for 40% of the time.
The motherboard controls the speed of PWM fans according to temperature readings from various parts of the PC, but primarily the CPU. In addition, the way that PWM fans are controlled means that they can achieve much lower speeds than DC fans.
DC vs. PWM Fans: Key Differences
Despite being very similar, the differences between DC and PWM fans may make them better for different applications. However, keep in mind that there are many more important aspects to consider when choosing the best case fan for you.
Related: How to Choose the Best Case Fans for Your Custom PC
Number of Pins
DC fans have three pins:
- 12V power supply pin
- Grounding pin
- Tachometer pin
PWM fans have four pins:
- 12V power supply pin
- Grounding pin
- Tachometer pin
- PWM pin
Fan Speed Control
DC fan speed is adjustable by limiting the voltage supplied to the pin. In contrast, PWM fan speed is controlled by precisely turning the fan motor on and off during duty cycles. DC speed control isn’t as refined as PWM, but this aspect doesn’t take much from its effectiveness, especially in the latest models.
Essentially, you have far more control over PWM fan speed, though it’s becoming more common to see DC fans with control knobs.
Minimum Fan Speed
Since the DC fan is slowed by reducing its voltage, it can stall below a certain voltage threshold. This occurs when there isn’t enough power supply to keep the fan moving. With PWM fans, you can achieve a much lower fan speed by reducing the duty cycle.
Another bonus is that PWM fans will never stall since their entire function is to turn on and off repetitively.
Noise
A side-effect of the greater speed control that PWM fans provide is that while the computer doesn’t need the extra cooling, it will spin far slower and produce far less noise than DC fans. Since DC fans typically run faster than PWM fans while idling, they are louder.
Another thing to remember is that some DC models will generate electrical noise (one of those strange PC noises that occasionally arise) while they aren’t operating at 12V. Since PWM fans always run at 12V, this isn’t an issue.
However, differences in the noise level will be minuscule during peak PC performance. The main thing that determines the noisiness is the fan’s maximum RPM and its overall build quality.
Cost
DC fans generally cost less than their PWM cousins since they’re cheaper to produce. So, if the price is the main deciding factor for you, DC is easily the better choice.
Power Consumption
Due to the way PWM fans function, they’re generally more efficient than DC fans and use less power. Consider the duty cycles of PWM fans. When a fan is on a 40% duty cycle, it’s only using electrical power 40% of the time. In comparison, the DC fans, if anything, will use a slightly lower voltage.
Primary Uses
DC fans are more commonly used as case fans or in situations where the system is likely to need to maintain 100% fan speed, such as in the case of a 24/7 server. PWM fans are more valuable if noise is a significant concern or if you’re looking for maximum power efficiency in your setup.
Which Fan Is Better?
Over the years, technology has improved to the point that there aren’t many reasons to prefer one over the other for the average person.
PWM fans will usually set you back more, but use less power and produce less noise. DC fans are likely just as effective and cheaper, but they will also be noisier.
One thing to consider is the number of 4-pin connectors on your motherboard. If you have plenty, you may want to stock up on PWM fans, as these are slightly more effective. However, if you’re looking for case fans (and noise isn’t an issue), there’s no reason not to go with the cheaper DC fans.
What is PWM and how does it work?
*Updated 3rd of October 2019.*
The option of controlling the fan speed and the satisfaction of silent computing were not always present when it comes to personal computers. The early x86 computers did not have active cooling because not much heat was generated, right until the introduction of the first 486 models. From that time and up until now, the computer power consumption and thermal dissipation have grown exponentially, as well as their performance.
From the very first Pentium processors that were declared at 7W TDP, and all the way down to the modern day AMD FX 9590 processor that is rated at 220W, the cooling also had its own evolutionary path. TDP stands for “Thermal Design Power” and it is the maximum amount of heat generated by the processor. If you are to stumble upon an abbreviation that you don’t understand, take a peek at our “Liquid cooling glossary” page and you just might find the correct answer!
4-pin PWM header can automatically control the speed of your fans and pumps.
Early homemade fan controllers used a simple “volt mod” by choosing 5, 7 or 12V from a classic molex connector. It was followed by the use of ordinary resistors to slow the fans down, fans equipped with thermal resistors, various potentiometers for a wide range manual speed control, etc.
But nowadays, if you want to control the speed of your fans and pumps, PWM control is the way to go. Every mainstream motherboard that leaves the factory today is equipped with at least one 4-pin PWM header. High-end motherboards offer 4-6 or even more of these 4-pin fan/pump connectors, and the PWM system is a very effective and smart way to control the fans. However, even today, many years after the introduction of PWM in 2003, there are users that are still not familiar with its advantages. And worse, there are serious companies out there that make advanced and well-designed fans with old-fashioned 3-pin connectors.
Therefore, we will explain what PWM actually is, how it controls the speed of fans and pumps, and we will also show you an example of a PWM profile in one of the software provided by the motherboard manufacturers.
By the number of wires – pins that a fan has – we can distinguish three main types of connections. Fans with only two wires have only plus and minus (ground) connections and that’s it. The second type has three wires; two for powering the fan and one that carries the so-called “Tach” or tachometric signal (in English: the wire that gives a readout of the current fan speed). A signal is sent via this third wire with a certain frequency that is proportional to the fan speed, expressed in RPM (revolutions per minute). The third type of fans that use four wires are PWM fans and that is what will be discussed in this article, along with PWM pumps.
PWM (Pulse Width Modulation) or modulation with the width of an impulse, is a widespread term in the world of electrical engineering. It has a broad range of application, like in the field of telecommunications, audio equipment, servo motors, etc. Interesting for us enthusiasts is the application of PWM in voltage regulation. If you’ve followed our recent blog article on MOSFETs and VRMs, you know what we are talking about. Some of you probably already know the principle on which pulse width modulation (PWM) works, but nevertheless, we will explain how it actually controls the speed of a fan or a pump.
In short, PWM operates like a switch which constantly cycles on and off, thereby regulating the amount of power the fan or pump motor gains. The PWM system that is used for controlling fans and pumps works with the motor, either getting +12V (full power) or 0V (no power). To have a better understanding how this works, take a look at the chart bellow.
So, the motor is being fed impulses of power. Imagine it the same way as if you were to turn the wheel with your hand. You can push the wheel every 5 seconds with the same amount of force, and you will keep the wheel spinning. You can also speed up the interval when you are pushing the wheel; let’s say you nudge it every 3 seconds. In that case, you would notice that the wheel is spinning a bit faster, and in almost the same way is how the Pulse Width Modulation works. The speed of the motor, i.e. the fan or pump, is determined by the width of the PWM signal – the length of the time it is powered on.
As seen on the chart above, a 10% duty cycle gives just a few impulses of power over a period of time, meaning that the motor will spin slowly, and a 100% duty cycle means that the fan/pump will work at full speed, constantly being powered on.
It is important to know that there is no voltage regulation involved here, and by using PWM regulation the motor is constantly being fed 12 volts. For that reason, the 4-pin motherboard header should be used only for one fan, or eventually two, by using the Y-splitter. Pumps for water cooling have significantly bigger power consumption, so the power is mostly hooked up to the molex connector, and the other two tach and PWM wires are connected to the motherboard header for PWM control and speed readout.
If no PWM signal is present, almost all fans will work on 100% of power, while most pumps used in water cooling will operate at some medium speed. Meaning, if you want to run the pump on full power, you need to hook it up to a PWM signal that is set on 100% duty cycle.
More quality fans have their own special IC driver chips within the motor hub that generate a sloped PWM signal instead of a flat square one. Flat square signals tend to create unpleasant clicking noises when the fan runs at low speeds. The sudden rise of power when the motor is given +12 volts results in the rotor being jerked, which in some cases creates the clicking sound. The use of special ICs makes sure that the motor is powered on more gently each time an impulse is given. This is not something you really need to know, but it’s here for you to understand why quality PWM fans cost a bit more.
Why is PWM so important? Well, almost all fans „die“ if the voltage is lowered under 5V, but with PWM control, the fans can reach really low operation speeds of 300-600 RPM. They don’t die literally; they just shut down and stop spinning, and that is why often the declared speed range of the fan can only be achieved by using PWM regulation. At these speeds, the fans are dead silent, and some fans can even be turned off completely via PWM regulation. One more very cool thing about PWM regulation is that you can use one PWM signal to govern all of your fans. Since the fans are getting 12 volts all the time, you can use special fan hub splitters that will send one PWM signal to all of the connected fans or even pumps. This way, all of your fans and pumps will work in harmony.
Let’s take a look at some software that motherboard manufacturers provide for PWM regulation. Almost every motherboard manufacturer has got the PWM regulation story very serious, and that’s why we have very detailed settings available, which is really good. All your „noise producing“ components can be kept at low speeds and you can set the PWM duty cycle curve according to the temperature readouts. In the Gigabyte EasyTune example given above, the PWM profile is set to run the fans on about 55% of speed when the CPU temperature is 60°C or lower. When the temperature reaches 70°C, the fans will speed up to 100% duty cycle. Simple and very efficient way to get a silent computer, of course, if you are equipped with quality PWM fans and quality PWM pumps.
All EK products, for example, fans and pumps, have PWM feature and you just have to look for the following icon in our Shop! ?
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Fans for Liquid Cooling: What you need to know XForma MKII by Derick Magnusen
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PWM vs. DC vs. Auto Fan Modes for System & Case Fans
If you’ve ever gone rummaging through your BIOS, you might have stumbled across the terms PWM, DC, and Auto in the fan control section.
In this article, I’ll go over PWM vs. DC mode fans and what modes to use for effective cooling and low noise levels.
PWM vs. DC vs. Auto Fan Modes
The Short Answer – DC or PWM Mode?
Before getting started on the explanation, I’ll condense it down for those who want a quick answer.
If you have a 3-pin fan connector, pick DC mode. On the other hand, if you have a 4-pin fan connector, select PWM mode.
If your motherboard fan header only has 3 pins, pick DC regardless of whether you have a 4-pin PWM or 3-pin DC fan.
If you want to find out more about these mysterious terms, read on!
What is PWM and How Does it Work?
PWM (Pulse Width Modulation) fans allow motherboards to control fan speeds using rapid power pulses (on-off cycles). Simply put, a PWM fan turns off and on very fast to run at lower speeds.
This type of fan requires a 4-pin fan connector like the one shown below:
As you can see in the PWM fan pin diagram above, the 4th pin (blue) allows the motherboard to send a PWM signal to the fan, which controls its speed.
Steady pulses of power are used to vary fan speeds in PWM mode, which means that the fan motor switches from the ON to OFF state and back to ON rapidly.
However, the voltage (12V) applied to a PWM fan won’t change regardless of fan speed when in this mode.
So, the power delivery graph for a PWM fan looks something like this (called a square wave or pulse wave) –
See those power upticks (camel humps) on every duty cycle? Those are pulses that keep the fan speed to what’s needed by a system.
So, a 10% fan speed effectively means that a fan is ‘on’ only for 10% of the total time it’s running.
Thanks to this behavior, PWM fans can typically achieve much lower speeds than their DC counterparts while lowering power consumption in the process.
Note – Some premium PWM fans can also contain components that will ‘smoothen’ out this square signal a bit, giving it an upward and/or downward slant each time a pulse is detected.
What are DC Fans? How do they Work?
DC (Direct Current) fans are a bit different. For one, they come equipped with a 3-pin connector like this one:
As you can see, the 4th pinout is missing on DC fans.
While PWM fans rely on sending the same voltage (12V) through a fan but turn the power ‘on and off’ rapidly to achieve lower speeds, DC fans can only change speeds by varying the voltage applied to it.
This means that a DC fan will run at full speed when a voltage of 12V is applied to it but will slow down when this voltage is only, say, 7V.
That said, these fans are still limited by a minimum threshold voltage needed to keep the fan spinning, which limits the minimum speeds they can achieve.
For example, here’s a graph that illustrates how a DC fan’s speed (in %) varies with applied voltage:
Well, what about the AUTO mode?
Picking AUTO will leave the choice up to your motherboard to detect and deliver the correct kind of power to a fan.
However, this automatic choice CAN be wrong, so if you’re noticing any strange fan speed behavior, go ahead and change it manually.
What Mode to Pick – DC or PWM?
Now, the above section has probably given you a clue about what happens when picking the wrong mode for a fan.
If you have a DC fan, and you’ve selected PWM mode on that fan header, the fan will ALWAYS receive a voltage of 12V. It just doesn’t have that 4th pin to recognize or control pulses, and you end up with a fan that works at 100% all the time.
If you’ve noticed your PC fans spin at full speed on startup before quieting down, this is why – on some boards (mostly older ones), there’s a short delay on waking from a cold start when a full 12V is applied to the fan header before settling into PWM mode. This is one reason for that annoying ‘rev’ when your PC boots up.
Now, on the flip side, what happens if you pick DC mode for a 4-pin PWM fan? Well, nothing very interesting. It just ends up working as a regular DC fan. You will be limited to a certain minimum speed, but other than that, it’ll work just fine.
PWM vs.
DC Fan Noise
PWM fans will generally be quieter than DC fans because sometimes you’ll hear more electrical noise in some motors when they operate below a specific voltage.
Moreover, as I said above, PWM fans can achieve much lower speeds, which again helps with the noise.
DC fans are cheaper to manufacture, and you’ll see them extensively used in systems that are meant to keep fans at a full 100% speed.
Servers are a great example here.
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Noctua
Noctua offers a wide selection of fans for various demands and purposes. Use the following criteria to select the model that works best for you:
- Size and shape: The first thing you should determine is what size and shape of fan you need. For example, you might need a 120mm size fan for your water cooling radiator vs a 40mm size fan for your router. Note that for some sizes there are different shapes (e. g. square frame and round frame for 140mm size) and depths (e.g. 25mm and 15mm for 120mm size, 20mm and 10mm for 40mm size, etc.) available, so also check which shape and depth is required (e.g. round frame fans for most 140mm CPU coolers vs square frame fans for most 140mm water cooling radiators). If you have enough space, always choose the bigger depth fan (e.g. 120x25mm rather than 120x15mm) for the best possible performance.
- Voltage: Most Noctua fans are 12V, which is the standard for PC applications. Note, though, that there are also 5V and 24V models available for other applications. The latter can easily be recognised by the «5V» or «industrialPPC-24V» designations.
- Product line and colour scheme: In addition to the standard line of premium-quality quiet fans that is easily recognisable by the signature brown colour scheme, Noctua offers 3 dedicated product lines for specific demands:
- redux: streamlined, more affordable packages for price-conscious users, grey colour scheme
- chromax: black fans with swappable anti-vibration pads in various colours, ideal for coordinating the fans with individual build colour scheme
- industrialPPC: ruggedised high-speed versions for challenging environments, black colour scheme
- Connector: Noctua fans are available with standard 3-pin and 4-pin PWM connectors. The latter can be identified by the “PWM” designation. Choose 4-pin PWM versions if you would like to use the PWM fan speed control of your motherboard (or other devices). The 3-pin versions can only be speed-controlled by reducing the voltage (or using the supplied Low-Noise Adaptors in the case of FLX and ULN versions). However, as explained in this FAQ, 3-pin fans can also be used on most 4-pin headers and vice versa. Note that some models also come with adaptors for 4-pin peripheral connectors, 2-pin or USB connectors, or the OmniJoinTM adaptor set that allows the fan to be connected to proprietary fan headers. Please refer to the specifications of the individual models for details.
- Noise level and RPM speed: Please refer to the dB(A) specification of each individual model for selecting one that fits your requirements regarding noise and performance. In general, higher RPM speeds result in higher noise levels, but note that the relation of RPM speed and noise differs from fan size to fan size (e. g. a 2000rpm 40mm fan may be quieter than a 1500rpm 120mm fan) and from fan design to fan design (e.g. the NF-S12A 120mm fan at 1200rpm is quieter than the NF-F12 120mm fan at 1200rpm), so always refer to our dB(A) specifications rather than to RPM speeds only. In the different product lines, we use different designations for highlighting the fans’ speeds and noise levels:
- standard line: HS-PWM versions are the highest speeds in this line, PWM and FLX versions are high to moderate speeds and ULN versions are the lowest speeds
- redux: Speeds are designated in the product name numerically, e.g. NF-S12B redux-700 is 700rpm, NF-S12B redux-1200 is 1200rpm.
- chromax: There is only one speed per fan version in the chromax line.
- industrialPPC: Speeds are designated in the product name numerically, e.g. NF-F12 industrialPPC-2000 is 2000rpm, NF-F12 industrialPPC-3000 is 3000rpm.
- Accessories: Redux and industrialPPC line fans come with mounting screws only whereas the standard-line fans come with a rich bundle of accessories (different cables, adaptors, anti-vibration mounts, etc. , see individual specifications for details). The chromax line fans come with mounting screws and swappable anti-vibration pads in different colours.
- Performance and application-type considerations for 120mm fans (airflow vs static pressure): In the 120mm range, Noctua offers the NF-A12x25 that provides superior performance in all applications and models such as the NF-F12 and NF-S12A or NF-P12 redux and NF-S12B redux that are focused solutions for either airflow or pressure-demanding applications. See this guide for further explanations. Note that there is no distinction between airflow and pressure-focused models in all other sizes. Except for the NF-F12, NF-P12 and NF-S12 lines, all other Noctua fans are designed to provide optimal results in both types of applications. In particular, Noctua’s A-series models are universal solutions that are excellent both as case fans and on coolers and radiators.
- Popular choices and recommendations: Still undecided? Here’s a list of our most popular models of each size that have proven to work extremely well for the vast majority of users:
- 140mm: NF-A14 PWM
- 120mm: NF-A12x25 PWM
- 92mm: NF-A9 PWM
- 80mm: NF-A8 PWM
- 60mm: NF-A6x25 PWM
- 40mm: NF-A4x10 FLX
Still unsure which model to buy? If you have any further questions, please feel free to contact us at support@noctua. at.
Arctic F12 PWM Fan
Arctic F12 PWM Fan Discontinued |
|
More variations available Show |
Arctic’s PWM case fans are a little different to normal PWM fans. This is thanks to the patented PST (PWM Sharing Technology). The PST feature allows up to five of these fans to be daisy chained together.
High Performance Ultra Quiet PWM Case Fans
Arctic’s PWM case fans are a little different to normal PWM fans. This is thanks to the patented PST (PWM Sharing Technology). The PST feature allows up to five of these fans to be daisy chained together, meaning the motherboard can power and regulate all five fans from one PWM fan header from the motherboard.
Features
- Patented PWM Sharing Technology (PST)
- Extremely quiet
- High air flow and static pressure
- Low noise impeller
- Fluid dynamic bearing extends service life
How does PST lower the temperature of the entire case?
CPU and graphics cards generate an increasing amount of heat which leads to high ambient case temperatures. Some users will use more case fans to keep the heat under control. However, this often produces more noise, and energy will be wasted as all fans run at full speed even after the case temperature is lowered.
Using the new ARCTIC PWM fans can solve these problems with little hassle. The fan speed of these fans can change according to system temperatures thanks to motherboards BIOS features. Furthermore, the innovative patented PST function can allow up to five fans (including CPU fans) to be connected to the ARCTIC PWM fan. The speed of all the fans in this PST system is now centrally controlled by a single PWM signal via BIOS.
As a result, when the system temperatures increases, all fans in the PST system will run faster to lower the temperature. Likewise, when the temperatures decrease the fan speed will be lowered accordingly. This is ideal if you want to maintain cooling during high load but require quieter cooling during idle periods.
In conclusion, the advantages of PST are:
- Control the speed of different fans with only one PWM signal from the mainboard.
- Case ventilation can be achieved in a quiet and efficient way. More fans run slower at idle, which deliver sufficient cooling at a much quieter operation than before.
- Better energy saving as fans are not always at full load.
PLEASE NOTE — Arctic Cooling measure noise levels in Sone (loudness) instead of dB (sound intensity). The loudness depends upon your ears response curves and tells you how noticeable a certain noise is.
Specifications | Arctic F12 PWM |
---|---|
Dimensions | 120 L x 120 W x 25 H mm |
Rated Fan Speed | 300 — 1350RPM (controlled by PWM) |
Air Flow | 57 CFM / 96.8 m3/h |
Noise Level | 0.5 Sone (approx 25 dBA) |
Weight | 108 g |
Bearing | Fluid Dynamic Bearing |
Warranty | 72 months |
Specifications | Arctic F12 PWM |
---|---|
Dimensions | 120 L x 120 W x 25 H mm |
Rated Fan Speed | 300 — 1350RPM (controlled by PWM) |
Air Flow | 57 CFM / 96. 8 m3/h |
Noise Level | 0.5 Sone (approx 25 dBA) |
Weight | 108 g |
Bearing | Fluid Dynamic Bearing |
Warranty | 72 months |
See Also
Arctic Cooling Ultra-Quiet Fans
Quiet Fans
Product Resources
- Arctic Cooling website
FAQ
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How do I measure fan size?
The size of fan you need will generally be determined by the size of the fan fitting position in your PC case. The sizes of all the fans on our website are shown as measured along any one of the fan’s four sides, NOT the distance between the fan’s screw holes! Our most popular fan size is 120mm, followed by 80mm. This isn’t really dictated by customer preference, but more by recent designs of PC cases.
As for the thickness (depth) of the fan, generally 25mm (1 inch) is by far the most common depth, although smaller fans can have shallower depths such as 15mm or even 10mm. All our fans are 25mm thick unless otherwise stated. If you have any questions about which fan you should order, please don’t hesitate to get in touch.
If you know the distance between the fan mounting screw holes but don’t know what fan size to order, please see the following table. Note that the mounting hole measurements shown below are taken horizontally or vertically between the holes and not diagonally.
Screw hole spacings and fan sizes
Space Between Screw Holes Fan Size 32mm 40mm 40mm 50mm 50mm 60mm 60mm 70mm 72mm 80mm 83mm 92mm 105mm 120mm -
I received a small cable (resistor) with my fan; what is it for?
The resistor cable (also called Ultra Low Noise or ULN cable) is designed to allow the fan to run slightly slower for even quieter operation. The benefit in lower running noise is significant. Although the airflow will be reduced slightly, this usually has minimal effect on PC temperature. We would generally recommend using the ULN resistor cable for best results in almost all circumstances.
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How can I tell which way the air blows through the fan?
Hold the fan so that the round fan sticker is facing you. You are looking at the rear of the fan. When you plug the fan in, the air will be blowing towards you. If you want a fan to act as an air intake, then the fan sticker will be facing the inside of the case. Some fans also have two small arrows moulded into their plastic housing — one arrow shows the direction of airflow, and the other (at 90°) shows the direction of blade rotation.
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Is it possible to use a 4-pin PWM fan or CPU cooler with a motherboard which has only 3-pin fan headers on it?
Electrically, there is no problem doing this — the fourth pin on the fan cable is used purely for PWM control and is not needed in order for the fan to run. So you can plug the 4-pin fan connector onto the 3-pin motherboard fan header, leaving the fourth pin not connected to anything. The fan will potentially run at full speed, so if you would like to reduce the speed of the fan you will need to adjust the fan speed setting in your BIOS or use fan control software such as SpeedFan in Windows.
The only other problem to consider is that occasionally, components immediately adjacent to the motherboard fan header can get in the way of the larger 4-pin fan connector, physically preventing connection. This problem also occurs if you try to use an in-line fan speed controller such as the one made by Gelid.
Another avenue to explore is the possibility of using a bay-mounted fan controller. Several models are available now which provide 4-pin fan headers, so this is an easy way to use 4-pin PWM fans in a PC system which has only 3-pin fan headers on its motherboards. When using this method, you may find it necessary to disable any fan warning settings in your motherboard BIOS, since the motherboard may incorrectly believe that its CPU fan has failed when the fan is connected to a fan controller rather than directly to the motherboard itself.
Top Ultra-Quiet 120mm fans
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Thank you
Steve
(Review via Trustpilot)
PWM Cooling Fan Controller | 2 Schemes
Contents
- 1 Types of DC fans
- 2 PWM fans and control rules
- 3 Homemade PWM cooler controller diagram
Good time everyone. Now we will talk about speed control of cooling fans with PWM — pulse-width modulation (PWM). We will also study a practical design of a controller circuit for a fan or high-power LEDs, which can be made from several parts.
Recently there has been a growing interest in driver circuits for controlling the speed of cooling fans used in electronic equipment. The simplest two-wire driver is an on/off circuit that starts the fan with a control signal when the sensor temperature exceeds a threshold and stops it when the temperature drops below the threshold.
More advanced versions of the drivers use a linear voltage control circuit in which the constant voltage applied to the fan is varied by means of a voltage regulator. To make the fan run at a lower speed, the voltage is reduced, and to run at a higher speed, it is increased.
The most modern driver circuit for fan speed control uses the PWM method. In this driver circuit, the PWM control signal is typically applied to a FET that is connected to the high or low side of the fan. The fan will turn on/off at a certain frequency, and the fan speed is controlled by the duty cycle of the PWM signal.
Types of DC Fans
There are three main types of DC fans (aka coolers): 2-wire, 3-wire, and 4-wire.
- The two-wire fan has two contacts — power and ground. This fan can be controlled either by varying the DC voltage or by a PWM control signal.
- The 3-wire fan has a tachometer signal that indicates rotational speed. This fan can also be controlled by varying the DC voltage or using a low frequency PWM control signal.
- The 4-wire fan has a dedicated PWM input that can be used for speed control.
PWM fans and control rules
The square wave PWM signal must be applied to the PWM input of the fan and must meet the following specifications:
- Target frequency: 25 kHz, allowable range is 21 kHz to 28 kHz
- Maximum voltage for logic low: VIL = 0.8 V
- Absolute maximum current received: Imax = 5 mA (short circuit current)
- Absolute maximum voltage level: Vmax = 5.25 V (open circuit voltage)
- Allowable duty cycle range: 0% to 100% (not invertible. 100% PWM/5V duty cycle results in maximum fan speed)
An external pull-up resistor is not needed here as the signal is pulled up to 3.3V/5V inside the fan. Also, operation below 20% PWM cycle is not officially supported in the spec (undefined behavior). However, most PWM fans can run below 20% load and stop at only 0% duty cycle. They operate at full rated speed with no PWM input.
Attention: Connecting the 12V supply voltage to the PWM pin will damage the fan immediately!
The following is a picture of a 3-wire cooler. It appears to be a conventional brushless DC (BLDC) motor with a tacho signal output, but it is a PWM fan (KFB-1412H by Delta Electronics) made for the PS3, and its third wire is for fan speed control.
If you need to connect this fan, just apply 12V to the brown (+V) and black (GND) wires, and to the gray (PWM) apply a TTL level (5V) pulse train close to 25kHz from the generator signal , and change the pulse train duty cycle (0-100%) to adjust the speed.
Normally the speed of a PWM cooler is scaled linearly with the duty cycle of the PWM signal between the maximum speed at 100% and the specified minimum speed at 20%. For example, if a PWM fan has a maximum speed of 2000 rpm and a minimum speed of 450 rpm, it will run at 2000 rpm at 100% PWM, 450 rpm at 20%, and about 1100 rpm at 50 % PWM.
Some manufacturers recommend using a CMOS inverter type circuit like the one shown above for driving.
Homemade PWM cooler controller circuit
The main PWM output is connected to a power transistor (T1) to drive a 12V load. As you can see, an additional inverted PWM output is also available for other purposes. In fact, such a powerful transistor TIP41C (T1) in this design is a bit redundant, you can choose another one.
I’ve used this circuit to «linear» voltage control a 2-wire 12V BLDC fan and it worked great.
The six-element Schmitt trigger CD 40106 is the basis of this project. The chip is inexpensive and will operate over a wide voltage range.
The CD4016 (CD4016B / CD40106BE) contains six inverters that can be used to build simple square wave signal generators with a single resistor and capacitor. The input is connected to a capacitor that goes to ground, and a resistor goes from the output. With one potentiometer and two diodes, you can change the duty cycle or square wave pulse width. The potentiometer changes the way feedback flows through the two diodes, resulting in asymmetrical oscillation.
This simple design can be used to control various types of fans and lamps (including LEDs). The CD40106 square wave generator generates a control PWM based on the frequency and duty cycle set by the corresponding RC timing components. The final output signal can then be used in a variety of ways, provided it is configured correctly for the proposed device.
PWM fan speed controller on timer 555 —
Automatic 4-wire computer fan speed controller
This simple speed controller can be used to automatically control a 4-wire «smart» computer fan based on heatsink temperature. If you add a key on a field-effect or bipolar transistor to the circuit, then you can control a conventional 2- or 3-pin computer fan. Schema options will be discussed later in the article.
I used such a regulator in a small computer system unit — «nettop» Lenovo, in which for some reason it was not possible to use the processor cooling fan speed control built into the PWM board. Perhaps due to a hardware problem on the board, but most likely due to the lack of the necessary driver, the fan speed was always at a minimum and the processor overheated. That is, the motherboard did not increase the speed when the processor load increased and it heated up, as is usually the case in laptops and desktops. The use of third-party programs to control the fans did not work. All programs simply did not see the fan control chip.
However, this circuit can be successfully used in any device where cooling of circuit elements is required, for example, in a power supply or in an audio power amplifier. The principle of operation is to constantly monitor the temperature of the radiator of transistors or microcircuits and increase the speed of rotation of the fan blades in proportion to the temperature increase.
There are several types of «computer» fans according to the connection and control method:
The simplest is 2 wires. Plus and minus the supply voltage of 12 volts. Often such fans are used in inexpensive computer power supplies. You can control the rotation speed of such a fan by changing its supply voltage. There is no speed control.
The next type is a fan with 3 wires. It differs from two-wire in the presence of a third wire, through which a signal from the rotation sensor is transmitted. Thus, the computer motherboard or other device to which the fan is connected can “know” about the fan speed. If, for example, the fan breaks down and stops spinning, then the signals from the rotation sensor on the third wire will disappear. In this case, the motherboard will shut down to prevent processor damage due to overheating. You can control the speed of such a fan in the same way as in the case of a 2-wire — changing the supply voltage or using PWM — regulation.
The third type is a fan with four wires. This is the most advanced type of control. Usually used in more expensive and high-quality fans. This is the fan that was used in my nettop. We will analyze his work in more detail later.
fourth connection type is a variation of the first two-wire connection, using a standard MOLEX connector. Typically, fans with these connectors are used for installation in computer cases to improve cooling inside the computer. The +5V MOLEX wire is not used in simple fans, but sometimes it can be used to power an additional controller if the fan is sold complete with a speed controller. But most often only +12 and GND are involved.
4-wire fan operation
In order to make the 4-pin fan work, do the following:
- connect the black wire to the minus of the power supply (ground)
- connect the yellow wire 3 +12 of the power supply. In this case, depending on the type of fan, it will not spin at all, or it will rotate at the lowest speed
- Apply control pulses from the generator or PWM controller to the blue wire. These should be rectangular pulses with an amplitude of 4 to 12 volts and a frequency of several hundred hertz to several kilohertz.
The fan can operate at a frequency of control pulses in a fairly wide range. The determining factor is not the frequency of the pulses, but their duty cycle. The greater the percentage of pulse filling, the higher the rotation speed. Actually, like any fan connected to the PWM controller via a transistor switch. The only difference is that this field-effect transistor switch is built into the fan and an external one is no longer required. By applying impulses to the blue wire, we just control this key built into the fan.
The rotation speed is also somewhat dependent on the pulse frequency. At a higher frequency and with the same duty cycle, the fan speed will be slightly higher. When powered from the computer motherboard, the pulse repetition rates are usually around 10 kHz, but the fan will work fine even at a pulse frequency of, for example, 400. .500 Hz. In my NE555 controller, the pulse frequency is around 1..4 kHz, depending on the circuit settings.
Four-wire fan speed controller circuit
A four-wire fan is connected as follows:
- black wire — minus 12 volt supply (ground)
- yellow wire — to a source of plus 12 volts
- if you need to measure the fan speed, then the third, green wire is connected to the corresponding circuit. Or leave it unconnected
- We connect the blue wire to the output of our device (to the right terminal of the resistor R2 with a resistance of 27 Ohm
In the case of my computer, I simply cut the blue wire that went from the fan to the motherboard and gave it a signal from this The remaining 3 wires remained connected to the connector on the motherboard of the nettop.0003
The basis of the regulator is a multivibrator on the NE555 chip. A Chinese thermistor with a nominal resistance of 100 k is used as a thermal sensor. Such thermistors are used to control the temperature in the tables of 3D printers. They are very cheap, on aliexpress you can order a batch of 10 or 20 pieces. The thermistor has a very small size and, accordingly, a small inertia. It is very convenient for our purposes. The wire leads of the thermistor do not have insulation, so you need to put pieces of heat shrink tubing on them
Glue the thermistor to the radiator with epoxy glue.
At room temperature, the resistance of the thermistor is in the region of 100 kilo-ohms. At the same time, with the resistance of the resistor R1 indicated on the diagram, the duty cycle of the output signal is close to 2. That is, the duty cycle = 0.5. This is the initial state in which the fan speed is minimal — necessary.
555 timer output waveform at room temperature
As the temperature at the controlled point increases, the resistance of the thermistor decreases and the duty cycle of the square wave at the output increases:
Output waveform at temperature increase
Fan speed increases accordingly. In each case, the required duty cycle adjustment range depends on your needs and on the parameters of a particular fan. Therefore, you need to configure the circuit separately for each fan and operating temperature range.
The setting can be done in the following sequence:
- Instead of resistor R1, we temporarily solder a tuning (or variable) resistor with a resistance of 300 — 500 kOhm
- We turn to obtain the required minimum fan speed
- Now we need to achieve the maximum temperature at the controlled point. If this is a computer processor heatsink, then we run some benchmark on the computer in order to load the processor 100%. If this is, for example, a cooling radiator for a power supply, then we load the power supply to the maximum. Etc.
- For about 10 … 15 minutes, we observe the operation of all this, adjusting the required maximum fan speed with a resistor so that the temperature does not exceed the maximum allowable.
- We measure the resistance of a variable resistor and solder a constant resistor of a close rating into the circuit instead.
- It may also be necessary to select (or even eliminate from the circuit) the resistor R3. Its resistance depends on the characteristics of the thermistor. The lower the resistance R3, the greater the dependence of the rotation speed on temperature changes.
Now about how to connect a two — or three — wire fan to this circuit. In this case, the fan must be connected through its power circuit
Scheme for using a conventional two or three wire fan
In addition to that indicated in the diagram, almost any MOSFET transistor of suitable power can be used as a key.
What if you only have a 10 kΩ thermistor? No problem. It is possible to adapt the circuit to work with such a thermistor (10 kΩ thermistors are very common). In order to use such a thermistor, you need to change some elements of the circuit. Here are the new denominations:
R1 should be a resistance of 20 to 22 kOhm
C1 should be a capacitance of 10 nF (0. 01 uF) from your specific fan).
How to control a fan — chipenable.ru
Compact electric fans, due to their low price, have been used to cool equipment for more than half a century. However, it is only in recent years that fan control technologies have developed significantly. This article describes how and why this development took place and suggests some useful solutions for developers.
One of the trends in electronics is the creation of compact devices with rich functionality. Therefore, most electronic components are getting smaller and smaller. One obvious example is modern laptops. The thickness and weight of laptops is significantly reduced, but the power consumption remains the same or increases. Another example is projection systems and television receivers.
In laptops most of the heat is generated by the processor, in a projector by the light source. This heat must be removed silently and efficiently from the system. The quietest way to get rid of heat is to use passive cooling components such as heatsinks or heatpipes. However, for many popular consumer devices, this method is inefficient and expensive.
Another way to remove heat is active cooling, using fans to create airflow around heated components. However, the fan is a source of noise and, in addition, increases the total power consumption of the device, which can be critical when powered by battery. Also, adding a fan increases the number of mechanical components in the system, which negatively affects the reliability of the product.
Fan speed control reduces the disadvantages described. Because running the fan at a lower speed reduces noise and power consumption and increases its life.
There are several types of fans and ways to control them. One way to classify fans would be:
1. 2-wire fans
2. 3-wire fans
3. 4-wire fans
The fan control methods discussed in this article are:
1 no control
2. on/ff control
3. linear control
4. low frequency pulse width modulation (PWM, PWM)
5. high frequency control
2-wire fans have only positive and ground outputs. In 3-wire fans, a tachometric output is added. This output contains a signal whose frequency is proportional to the fan speed. 4-wire fans, in addition to power outputs and a tachometric output, have a control input. A PWM signal is applied to this input and the pulse width of this signal determines the fan speed.
2-wire fans can be controlled by adjusting the supply voltage or the duty cycle of the PWM signal. However, without a tachometer signal, it is impossible to understand how fast the fan is rotating. This form of fan speed control is called open-loop.
3-wire fans can be controlled in the same way, but in this case we have feedback. You can analyze the tachosignal and set the required speed. This form of control is called a closed-loop.
If you control the fan by adjusting the supply voltage, the tacho signal will be in the form of a meander. And in this case, the tachosignal will always be valid as long as there is voltage on the fan. Such a signal is shown in Figure 1 (ideal tach).
When controlling the fan with PWM, the situation is more complicated. The tachometric fan output is usually an open collector. Therefore, the tachosignal will be valid only if there is voltage on the fan (on phase of the PWM signal), and if there is no voltage (off phase), it will be pulled up to a high logic level. Thus, the tacho signal becomes «chopped» by the PWM control signal, and it is no longer possible to reliably determine the rotation speed from it. This signal is shown in Figure 1 (tach).
Figure 1. Ideal tacho signal and tacho signal with external PWM control.
To solve this problem, it is necessary to periodically turn on the fan for such a period of time that will allow you to get several reliable cycles of the tacho signal. This approach is implemented in some Analog Device controllers, for example, in the ADM1031 and ADT7460.
4-wire fans have a PWM input that controls the switching of the fan windings to the positive bus of the power supply. Such a control scheme does not spoil the tachosignal, unlike the standard one, where an external key is used and the negative bus is switched. Switching fan windings creates switching noise. To «shift» this noise outside the audio range, the PWM frequency of the signal is usually chosen to be greater than 20 kHz.
Another advantage of 4-wire fans is the ability to set a low rotational speed — up to 10% of the maximum speed. Figure 2 shows the difference between 3 and 4 wire fans.
Figure 2. 3 and 4 wire fans
No control
The simplest method of fan control is no control at all. The fan just starts at maximum speed and runs all the time. The advantages of this control are guaranteed stable cooling and very simple external circuits. The disadvantages are reduced fan life, maximum power consumption even when no cooling is required, and continuous noise.
On/off control
The next simplest control method is thermostatic or on/off. In this case, the fan is turned on only when cooling is required. The condition for turning on the fan is set by the user, usually it is some kind of temperature threshold.
A suitable sensor for on/off control is the ADM1032. It has a THERM output which is driven by an internal comparator. In the normal state, this output is logic high, and when the temperature threshold is exceeded, it switches to low. Figure 3 shows an example circuit using the ADM1032.
Figure 3. Example of on/off control
The disadvantage of on/off control is its limitation. When the fan is turned on, it runs at maximum speed and makes noise. When turned off, it stops completely and the noise also stops. This is very noticeable by ear, so from the point of view of comfort, this method of control is far from optimal.
Linear control
In linear control, the fan speed is changed by changing the supply voltage. To get low speeds, the voltage is reduced, to get high, it is increased. Of course, there are certain limits for changing the supply voltage.
Consider, for example, a 12 volt fan. It needs at least 7 volts to start and at this voltage it will probably rotate at half the speed of its maximum value. When the fan is running, less voltage is needed to keep it spinning. To slow down the fan, we can lower the supply voltage, but up to a certain limit, say, up to 4 volts, after which the fan will stop. These values will differ depending on the manufacturer, fan model and specific instance.
5V fans allow for even smaller speed control, since their starting voltage is close to 5V. This is a fundamental disadvantage of this method.
Linear fan control can be implemented on the ADM1028 chip. It has a control analog output, an interface for connecting a diode temperature sensor, which is commonly used in processors and FPGAs, and operates from a voltage of 3 — 5.5 V. Figure 4 shows an example circuit for implementing linear control. The ADM1028 chip is connected to the DAC input.
Figure 4. Diagram for realizing the linear control of a 12V fan
The linear control method is quieter than the previous ones. However, as you can see, it provides a small range of fan speed control. 12-volt fans with a supply voltage of 7 to 12 V allow you to set the rotation speed from 1/2 from maximum to maximum. 5-volt fans, when started from 3.5 — 4 V, rotate at almost maximum speed and their control range is even smaller. In addition, the linear method of regulation is not optimal in terms of power consumption, because the reduction in the fan supply voltage is carried out due to power dissipation in the transistor (see Figure 4). And the last drawback is the relative high cost of the control circuit.
The most popular fan speed control method is PWM control. With this control method, the fan is connected to the negative power bus through the key, and a PWM signal is applied to the control input of the key. In this case, either zero or operating voltage is always applied to the fan, and there are no such energy losses as with the linear control method. Figure 5 shows a typical circuit that implements PWM control.
Figure 5. PWM control.
The advantage of this control method is ease of implementation, low cost, efficiency and a wide range of rotation speed control. However, this method also has disadvantages.
One of the disadvantages of PWM control is the «damage» of the tacho signal. This drawback can be eliminated using the so-called pulse stretching technique, that is, by extending the PWM signal pulse by several periods of the tacho signal. Of course, this may increase the fan speed slightly. Figure 6 shows an example.
Figure 6. Lengthening the pulse to obtain information about the rotational speed.
Another disadvantage of PWM control is switching noise. Firstly, switching an inductive load causes interference in the power circuits, and secondly, acoustic noise can occur — squeaking, buzzing. Electrical noise is suppressed by filters, and to combat acoustic noise, the PWM signal frequency is raised to 20 kHz.
Also worth mentioning again are the 4-wire fans, in which the control circuit is already integrated. In such fans, the positive power bus is switched, which helps to avoid problems with the tacho signal. One of the microcircuits designed to implement PWM control of 4-wire fans is the ADT7467. The conditional scheme is shown in Figure 7.
Figure 7. 4-wire fan PWM control circuit
In summary, the most preferred fan control method is high-frequency PWM control implemented in 4-wire fans. With such control, there is no acoustic noise, significant energy losses and problems with the tacho signal. In addition, it allows you to change the fan speed in a wide range. The PWM control circuit with negative bus switching has almost the same advantages and is cheaper, but spoils the tacho signal.
Courtesy of AnalogDevices.
Venturi HP-12 PWM — Fractal Design
Venturi PWM, HP-12 and HP-14 series high pressure fans optimized for applications with severe airflow restrictions.
These fans are equipped with a variety of performance enhancing and noise reducing features, enabling them to handle a larger volume of air in difficult environments than other fans.
The HP-14 comes with two sets of one piece shock absorbing rubber corners, one for standard 140mm (125mm) fan holes and one for standard 120mm (105mm) fan holes. Venturi PWM series high pressure fans are ideal for those looking for a balance between performance and quiet operation. Fans HP-14 are made of strong and high quality materials.
Key Features
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Fluid dynamic bearings for quiet operation and long service life
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Equipped with a balancing magnet that reduces bearing thrust
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Includes one-piece, high-quality synthetic rubber anti-vibration corners attached to fan
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Sturdy construction made of thermoplastic polymer reinforced with high grade
glass fiber
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The fan geometry is optimized to achieve high pressure, which ensures efficient operation with high density radiators and water cooling systems
-
Equipped with a PWM controller with a wide range of speed adjustment starting from 400 rpm (400 +/- 100 rpm), which is ideal for CPU heatsinks or heatsinks where the motherboard determines the fan speed according to the temperature of the CPU
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Slim, aerodynamically shaped stator reduces noise and unwanted turbulence
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Notches in special places near the fan hub further reduce and dissipate the humming noise produced when the blades pass near the stator mounts
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Features a special «trip wire» aerodynamic design that creates a layer of micro-turbulence that contributes to the quiet operation of the
fan
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Supplied with 1->2 PWM signal splitter cable for connecting additional fans to one PWM device on the motherboard or PWM fan controller
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140mm fans come with an additional set of anti-vibration brackets that provide compatibility with 120mm fan mounts (105mm screw spacing). This allows you to install 140mm fans on many CPU coolers
Fluid dynamic bearings for quiet operation and long life
Equipped with a balancing magnet that reduces bearing thrust
Includes one-piece, high-quality synthetic rubber anti-vibration corners attached to fan
«The good:
+ High quality felling and excellent product presentation
+ Metal plate for the rotor
+ Modular corners for increased adaptability (for the 140 mm)
+ Very good ratio of performance and noise output.
+ Good bundle
The bad:
– Price, but it should be worth it
– The fans could have had better static pressure»
Glob3trotters.com
Read the full review of
Specifications
-
Size
120 x 120 x 25mm
-
Screw hole pattern
105 x 105 mm
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Connector
4-pin
-
Bearing
FDB
-
Number of blades
7
-
Rotational speed
1800RPM
-
Noise level
31. 7 dB(A)
-
Airflow (CFM)
61.4
-
Airflow (m3/h)
104.3
-
Static pressure
2.3 mm h3O
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Fan input power
1.0W
-
Fan max input current
0.2A
-
Fan input voltage
12V
-
Fan starting voltage
6V
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Low (0-20%) PWM speed
400 RPM
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Low PWM noise level
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Low PWM airflow (CMF)
15.4
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Low PWM airflow (m3/h)
26.2
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Low PWM static pressure
0.45 mm h3O
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MTBF
150,000 hours
-
Fan weight
179 g
-
Cable length
500mm
-
Cable type
Braided all-black ribbon wire
Other
-
Package contents
Venturi Series fan, Screw pack with 4 metal screws, 1->2 PWM signal splitter cable
-
Package weight
225g
-
Package dimensions (Including hanging tab)
180 x 122 x 30 mm
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Package dimensions (Excluding hanging tab)
147 x 122 x 30 mm
-
EAN
7350041083344
-
Product code (Black)
FD-FAN-VENT-HP12-PWM-BK
-
Product code (White)
FD-FAN-VENT-HP12-PWM-WT
Downloads
PWM fan control
The unit generates the necessary fan control signal according to an energy-saving algorithm, using the readings of a standard or stand-alone analog ICE temperature sensor as an input signal. Select the product you need by setting the quantity different from 0. Before filling, please note: — If you do not have your own e-mail, then enter in this field This e-mail address is being protected from spambots. You must have JavaScript enabled to view. Make it, if possible, shorter, but understandable, for example: «N. Novgorod Primorskaya 1 building
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Content:
- How to control the CPU fan?
- What is the best way to make a multi-channel PWM (PWM) fan driver based on STM32?
- Prompt, engine cooling fan
- Cooler (cooling system)
- Fan control AC 220V
- Dear User!
- PWM fan control
WATCH RELATED VIDEO: How to reduce computer noise or friends 3-pin fan with pwm
How do I know if my fans support PWM?
If pin 4 is described as «Speed Control» or «PWM» or something similar, you can make sure the fan header supports PWM. Unfortunately, the pin 2 description isn’t always a clear indication as some manufacturers use terms like «Fan PWR» or «Power» for both types of fan headers.
Should all my fans be PWM?
The speed of non-PWM fans can still be adjusted using a mobile device or a dedicated fan controller. PWM fans are more energy efficient than (although I can’t imagine they will save you more than a few watts). I think a given PWM may have a lower minimum speed than an «equivalent» non-PWM fan, but non-PWM fans can still be quite slow.
How do I know if my fans are DC or PWM?
PWM fans or 4-pin fans
Pulse Width Modulated (PWM) fans DC fans with optional PWM wire . PWM fans are 4-pin fans whose fourth wire sends a PWM signal to the fan motor.
Do all motherboards support PWM fans?
yes , your motherboard (and most modern motherboards) supports PWM fans. From page 25 of the manual: Fan speed percentage. Allows you to control the fan speed.
Can PWM control RGB?
Dedicated Pulse Width Modulated (PWM) LED Controller
The circuit controls three outputs, each of which can drive an LED segment. Three separate outputs are natural for driving arrays of RGB LEDs.
Which is better DC or PWM?
The PWM fans are useful because they minimize noise and are more energy efficient than DC fans. Because of the way they function, the bearings in PWM fans will last a lot longer.
Which is better PWM or DC?
The main reason that PWM fans are better than DC fans is that they will spin at lower speeds. So if you can get enough airflow at those low rpms, then PWM fans are better.
PWM fans louder?
Champion. running RPM fans in pwm mode in BIOS often causes them to make noise . so try using auto mode or set them to RPM.
Can you control fan speed with 3 pins?
The speed of BOTH 3 and 4 pin fans can be controlled by , but the method is different for the two types. For 3-pin fans, connect to it: ground to pin #1, + VDC (variable) to pin #2 and speed signal on pin #3.
Ll120 DC or PWM?
The only fans you can’t run in DC are the Corsair ML fans, they must be PWM to power the magnetic system.
Can PWM fans be voltage controlled?
yes , the power supplied to the fan is the same. The inefficiency of non-PWM fans is due to the fact that they are controlled by a linear voltage regulator. If the linear regulator outputs anything less than the 12V input (full speed), it will dissipate excess power as waste heat.
PC fans 3 or 4 pins?
You are using 3-pin fans for case fans. They use variable voltage speed control. For custom cooling, usually the pump is controlled by the motherboard’s CPU fan connector (4-pin) and the heatsink fans are controlled either by the motherboard’s chassis fan connectors (3-pin) or by a module like the Corsair h200i.
Why do PWM fans have 4 pins?
Pulse Width Modulation
You will find PWM in control devices such as servomotors, dimmers, buzzers or as a telecom encoder. So why is there a 4-pin PWM header on the motherboard? The reason is quite simple: a 4 -pin PWM connector is used to control a cooling fan attached to the case.
Can I use a 4-pin fan on a 2-pin connector?
yes , the fan will work, but the fan speed will not be controlled by the motherboard, because the voltage cannot be regulated by just two pins.