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LED Lighting


4 or 3-Channel LED Driver With Grayscale Adaptive Pulse Density Modulation Control
General Description

*※Data Rate 10Mbps@10m (distance between pixels) ※

The MY9291, 4 or 3-channel (R/G/B/W or R/G/B/Amber or R/G/B x 1) constant current APDM LED driver, operates over a 3V ~ 5.5V input voltage range. The device provides 4 or 3(selectable) open-drain constant current sinking outputs that are rated to 17V and delivers up to 350mA of high accuracy current to each string of LED. The current at each output is programmable by means of four external current setting resistors.

MY9291 features a 10MHz EMI reduction data clock input. MY9291 also offers a 2-wire serial interface to send the grayscale data, control command including 16/14/12/8-bit grayscale selection, output polarity selection for high power LED driving grayscale clock frequency division selection, output Tr/Tf timing selection, current output waveform selection, and to realize the internal-latch function. MY9291 provides adaptive pulse density modulation method to increase the visual refresh rate up to 2000 Hz @ 16-bit grayscale and reduce the flickers, and it also provides output polarity selection for high power LED driving. Moreover MY9291 utilizes clock duty recovery technique and pulse re-timing to help long distance and multiple cascading applications. MY9291 provides typical ±1.5% channel-to-channel LED current accuracy. Additional features include a ±0.1% regulated output current capability and fast output transient response.

MY9291 is available in a QFN20,SSOP20 and TSSOP20(Exposed Pad) packages and specified over the -40°C to +85°C ambient temperature range.

keyword:3 or 4-Channel 16bits PWM LED Driver,MY9231,High power LED, Lighting controller,MY-Semi Inc.

  • Indoor and Outdoor LED Video Displays
  • Full Color Mesh Display 
  • Full Color Dot Matrix Module
  • Architectural and Decorative Lighting
  • LCD Display Backlighting
Typical Operating Circuits 

             MY9291_Operating circuits.jpg

  • 3V ~ 5.5V Operating supply voltage
  • R/G/B/W x1 or R/G/B/Amber x 1or R/G/B x1 Output Channels
  • 5~350mA Constant current output range
  • 17V Rated output channels for long LED strings
  • ±1.5% (typ.) LED Current accuracy between channels
  • ±3% (typ.) LED Current accuracy between chips
  • 20Mbps (max.) data rate for EMI reduction [ patent pending ] 
  • 16 / 14 / 12 / 8 bit grayscale selection
  • Built-in internal grayscale clock supports refresh rate >2000Hz@16-bit grayscale
  • Grayscale clock frequency selection for High Power LED driving application
  • Grayscale clock source selection: internal or external
  • PWM or APDM control selection [ patent pending ]
  • Clock duty recovery for cascading application
  • Current setting by 4 external resistors
  • Schmitt trigger input
  • Output Current Tr / Tf programmable
  • -40°C to +85°C Ambient temperature range
Order Information
MY9291SS SSOP20-150mil-0.635mm 2500 pcs/Reel
MY9291TE TSSOP20-173mil-0.65mm 2500 pcs/Reel
MY9291QD QFN20-4mmx4mm 3000 pcs/Reel
    Pin Configuration


    5F-5, No.6, Taiyuan 1st St., Zhubei City, Hsinchu County, Taiwan, 30288

    Telephone: 886 (3) 560-1668    Fax: 886 (3) 560-1600   Mail address: