Reference Design for the Tas5110dad Digital Audio PWM Power Output Stage:  The true digital audio amplifiers (TDAA) system consists of a PCM–PWM modulator device and a PWM power output device. The PCM–PWM processor accepts a serial PCM digital audio stream and converts it to a 3.3-V PWM audio stream. The TDAA output stage provides a large-signal PWM output. The digital PWM signal is then demodulated providing power output for driving loudspeakers. This patented technology provides low cost, high quality, high efficient digital audio applicable to many audio systems developed for the digital age. The TAS5110D6REF reference design demonstrates the integrated circuit TAS5110DAD from Texas Instruments (TI). The board does not contain any PWM processors. (added 6/06)

Servo Pulse to PWM:  converter connects an H-Bridge to radio control receivers or robotic circuits. (added 1/05)

Simple Circuit for Driving Microcontroller Friendly PWM Generators:  Microchip Application Note Published 27-Jun-05   (app note added 2/06)

Simple Circuit Provides Efficient PWM:  02/18/99 EDN-Design Ideas / (added 6/03) You often need to control the duty cycle of a square wave. The circuit in Figure 1 works from a single 5V supply at a frequency of 100 kHz. With minor component changes, you can configure it for a range of frequencies. The circuit consists of a ramp (sawtooth) oscillator and a comparator. The circuit compares the ramp to an externally applied voltage, VCNTRL. When VCNTRL is greater than the ramp voltage, the PWM output is 5V. The sawtooth oscillator consists of a current source (R1, R2, R3, and Q1), a timing capacitor (C1), and the oscillator-control circuitry (R4, R5, R6, and IC1A). The oscillator-control circuitry sets the upper and lower voltages of the timing capacitor at 3 and 1V....

Simple nanosecond width pulse generator provides high Performance:  11/11/04 EDN Design Ideas  / (added 5/05)  If you need to produce extremely fast pulses in response to an input and trigger, such as for sampling applications, the predictably programmable short-time-interval generator has broad uses. The circuit of Figure 1, built around a quad high-speed comparator and a high-speed gate, has settable 0to 10-nsec output width with 520-psec, 5V transitions.

Simple PWM ADC is Surprisingly Accurate:  06/09/94 EDN-Design Ideas / (added 3/03)  The reference voltage in Fig 1a's simple rail-to-rail PWM ADC is the only critical component. The input-voltage range extends from ground to the power rail which also acts as the reference. The circuit is essentially a variation on the classic dual-slope integrator, the slopes being proportional to VIN and VREF-VIN. The circuit works well in µP-based systems that have the spare capacity to perform the mark/space measurement and the necessary calculations.....   

Speed Error in PWM Fan Control Systems (TC646, TC647, TC649):  Microchip Application Note Published 27-Jul-04   (app note added 2/06)

Spice Model and PWM Amplifier Applications - App Note 33:  Apex Microtechnology Corp App Note (added 6/06)

Square-Wave modulator has variable frequency and pulse Width:  08/08/02 EDN Design Ideas (added 1/05)  A few years ago, I worked at a disk-drive company. We had a plating facility that required square waves to drive the high-voltage plating operation. The challenge was that the square wave's pulse width had to be variable, along with the duty cycle. Also, the amplitude of the pulses had to be adjustable....

Suppressing Acoustic Noise in PWM Fan Speed Control Systems:  Microchip Application Note Published 27-Jul-04   (app note added 2/06)

TB085: A Simple Circuit for Driving Microcontroller Friendly PWM Generators:  Microchip Application Note Published 27-Jun-05   (app note added 2/06)

TB093: Multiple PWM Output Soft-Start Controller:  Microchip Application Note Published 29-Nov-05   (app note added 2/06)

Transistor Pair Lowers PWM IC's Start up Current:  03/18/99 EDN-Design Ideas / (added 6/03) An auxiliary winding usually provides power for the popular UC384X-based offline switch-mode power supplies (SMPSs). This winding feeds the main PWM controller during steady-state operation. However, the controller always needs a small start-up current, which clearly plagues the efficiency in very low-power standby SMPSs with POUT =500 mW, for example. Any wasted source power, such as for the start-up network and controller supply, adds to the power drawn from the mains and significantly degrades the overall efficiency. Obtaining an acceptable efficiency at high line voltage represents a tough design task. Some tricks totally stop the start-up current by using a high-voltage bipolar or MOSFET (Reference 1). However, the....

Use a PWM fan controller in an EMI-susceptible circuit:  2/16/06  EDN Design Ideas  /  (added 11/06)  Control it with either an external negative-temperature-coefficient thermistor or a PIC microcontroller and its SMBus serial-data bus.

Using a Function Generator to Create Pulse Width Modulation (PWM) Waveforms:  Agilent Application Note   (added 6/06)

Using PWM to Generate Analog Output:  Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Using the PWM:  Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Variable Range PWM A/D for COP820CJ:  National Semiconductor Application Note   (app note added 2/06)

Variations on the PWM DC Motor Speed Control:  (electronic (schematic / circuit added 4/02)

Voltage Control with PWM Amplifier:  The EK01 provides an easy-to-use platform for the evaluation of a voltage control application using a PWM amplifier. The eval board is designed for surface mounting all components except the amplifier. (added 6/06)

Wireless RF PWM Dual Motor Controller:  (circuit / schematic design added 6/06)