This fourth pin transmits what is known as a pulse width modulation (PWM) signal, which switches the fan on and off quickly. While DC fans use different currents to control the fan speeds, ...

If your controller has 64 divisions available for the PWM function, this function's accuracy can be as low as 78 mV in a 5V system. With a microcontroller PWM generator, the clock sets the fundamental ...

He figured he get the fan to shut off by tweaking the PWM signal, but he found that he could not get the duty cycle under 20% using software, which still caused the fan to run at all times.

GPIOs P1.2 and P1.4 are configured as follows: P1.2 outputs the PWM signal and P1.4 outputs the system clock signal (SMCLK), which effectively is 50% duty cycle.

Class D amps are simple – just take an input, and use that to modulate a square wave with PWM. Send this PWM signal to a MOSFET or something, and you have the simplest class D amp in existence.

Pin 3: Tach signal from fan Pin 4: PWM signal from motherboard Most splitters I see online seem to have pin 3 connected to only one fan, which makes sense.

A logic gate IC, an op-amp, and a few resistors and capacitors buffer a PWM and supplies a signal to the regulator’s feedback pin, Figure 1. Figure 1 A microprocessor produces a 12-bit, 20 MHz, PWM ...

PWM signal that generates clocks This circuit transforms a pulse-width-modulation (PWM) signal into non-overlapping clock signals, whose number depends on the length of a shift register.

Having advocated Arduinos for prototype PWM signal generation, I have just discovered a subtlety that might trip up the unwary (amongst which I count myself). The original idea was not to use Arduino ...