What is pulse width modulation (PWM)?
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Pulse Width Modulation (PWM) is a way of digitally encoding analogue signal levels. Through the use of high-resolution counters, the duty cycle of a square wave is modulated to encode a specific analogue signal level. In more general terms, a switch is opened and closed in timed pulses, where the time the switch is closed is determines the power output. Basically, a PWM variable-power scheme switches the power quickly between fully ON and fully OFF tens or hundreds of kHz in the case of a computer power supply (which has a regulated output). The switching rate is much faster than what would affect the load. The term duty cycle describes the proportion of ON time to the regular interval or period of time. A low duty cycle corresponds to low power because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully ON. |
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| 2012-02-09 | LED drivers with PWM dimming for LCD backlight LED drivers with PWM dimming for LCD backlight |
| 2011-12-23 | How to use PWM mode 1 of SH7216 CPU How to use PWM mode 1 of SH7216 CPU |
| 2011-12-22 | Generate multiple PWM with DMA Generate multiple PWM with DMA |
| 2011-11-11 | Application guidelines for UBA3077HN LED driver Here are application guidelines for a 3-channel LED boost mode driver for lighting and LCD backlighting applications |
| 2011-10-25 | How to use LM5045 evaluation board Here's a look at LM5045 evaluation board designed to provide the design engineer with a fully functional power converter based on the full-bridge topology to evaluate the LM5045 PWM controller. |
| 2011-09-29 | POL chipset geared for high-performance apps ZMDI's ZSPM1000 and ZSPM9000 enable smart power management solutions for area constraint applications. |
| 2011-09-01 | Motor IC features LIN, PWM interface Motor IC features LIN, PWM interface |
| 2011-08-19 | PWM controllers boast up to 95% efficiency PWM controllers boast up to 95% efficiency |
| 2011-08-03 | PWM generator features 48 12bit resolution channels PWM generator features 48 12bit resolution channels |
| 2011-08-05 | How to use analog dimming with TPS6116x Find out how to perform analog dimming from PWM signals that are below 5kHz as well as from other analog sources using WLED drivers. |
| 2011-07-22 | Wide input flyback converter features 5V at 2.6A output Here's a reference design is for a flyback, 5V Class 3 powered device (PD) with a wide 9V to 57V auxiliary input. |
| 2011-06-27 | PWM controller saves space PWM controller saves space |
| 2011-05-12 | DrMOS solution enables 1MHz operating frequencies Vishay Intertechnology introduces the SiC779CD, an integrated DrMOS solution offering PWM-optimized high-side and low-side n-channel MOSFETs, a full-featured MOSFET driver IC and a bootstrap diode. |
| 2011-05-05 | Power controller device cuts wasted power iWatt releases the iW1700 Zero Power AC/DC Digital PWM Controller that eliminates wasted power and costs in offline chargers and adapters. |
| 2011-05-02 | Buck regulator gives 80mm2 footprint Semtech unveils the SC197 is a 500mA, dual-output, point-of-load (POL) regulator, combining two PWM DC/DC regulators in an ultra-small, low-profile 2x3x0.6mm package with an overall design solution footprint of 80mm2. |
| 2011-04-04 | LM5046 evaluation board The LM5046 evaluation board is designed to provide the design engineer with a fully functional power converter based on the phase-shifted full-bridge topology to evaluate the LM5046 PWM controller. |
| 2011-03-24 | Step-down LED driver offers 10,000:1 true color PWM dimming Step-down LED driver offers 10,000:1 true color PWM dimming |
| 2011-02-15 | PFC LED driver IC designed for space-constrained apps iWatt debuts its first power-factor-corrected (PFC) LED driver IC with primary-side-regulated, leading- and trailing-edge-dimmable, AC/DC Digital PWM Controller. |
| 2011-01-19 | Temp sensor IC enables efficient LED lighting Seiko Instruments Inc. (SII) launches the S-5855A Series of pulse width modulation (PWM) output temperature sensor IC for LED lighting designs. |
| 2010-12-27 | Buck-boost 2 layer evaluation board This wide range evaluation board showcases the LM3423 NFET controller used with a buck-boost current regulator. |
| 2010-11-11 | 2A PWM step-down converter optimized for 5V, 12V rail 2A PWM step-down converter optimized for 5V, 12V rail |
| 2010-09-24 | Dual step-down regulator supports up to 28V input, reduces BOM The ISL85033 from Intersil is a dual channel step-down regulator that lowers component count and maximizes design flexibility for high power-density industrial, communications and consumer electronics applications. |
| 2010-09-20 | NHET getting started This application note describes the basic steps necessary to generate a simple PWM with the next generation high-end timer (NHET) module. |
| 2010-08-09 | Emulating 16bit resolution for better LED intensity control in a video display This application note explains how to emulate 16bit PWM resolution for the video application by using the MAX6975 with a native PWM resolution of 14bits. |
| 2010-07-07 | How to apply additional PWM intensity control to LED drivers How to apply additional PWM intensity control to LED drivers |
| 2010-06-25 | Buck regulators integrate high-, low-side MOSFETs ON Semi's latest synchronous PWM switching buck regulators with integrated high side and low side MOSFETs are capable of delivering continuous output currents of 2A, 3A and 4A. |
| 2010-05-17 | HBLED driver integrates PWM dithering HBLED driver integrates PWM dithering |
| 2010-05-04 | LED driver with PWM eases dimming control LED driver with PWM eases dimming control |
| 2010-04-21 | Implementation of discontinuous PWM in TinyDIP/SMD SPM Implementation of discontinuous PWM in TinyDIP/SMD SPM |
| 2010-04-20 | Four-output PMIC packs 400kHz I²C Micrel Inc. has released a new four-output, programmable PMIC that integrates a single 500mA PWM/PFM synchronous buck regulator with three low dropout regulators in a tiny. |
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