MY9291
4 or 3-Channel LED Driver With Grayscale
Adaptive Pulse Density Modulation Control
MY-Semi
General Description
The MY9291,
Features
✦ 3 ~ 5.5V Operating supply voltage
4
or 3-channel (R/G/B/W or
R/G/B/Amber or R/G/B x 1) constant current
APDM (Adaptive Pulse Density Modulation)
LED driver, operates over a 3V ~ 5.5V input voltage
✦ R/G/B/W x1 or R/G/B/Amber x1 or R/G/B x1
Output Channels
range. The device provides
4
or 3(selectable)
✦ 5~350mA Constant current output range
✦ Current setting by 4 external resistors
✦ 17V Rated output channels for long LED strings
✦ ±1.5% (typ.) LED Current accuracy between channels
✦ ±2% (typ.) LED Current accuracy between chips
✦ 20Mbps(max.) ~ 220Kbps(min.) data rate for EMI
open-drain constant current sinking outputs that are
rated to 1 7 V 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
[ patent pending ]
[ patent pending ]
reduction data transfer [ patent pending ]
✦ 16 / 14 / 12 / 8 bit grayscale selection
✦ Built-in internal grayscale clock supports refresh rate
>2000Hz@16-bit grayscale, >512kHz@8-bit grayscale
✦ Grayscale clock frequency selection for High Power
LED driving application (min. 134.4KHz)
✦ Grayscale clock source selection: internal or external
[ patent pending ]
[ patent pending ]
✦ PWM or APDM control selection [ patent pending ]
distance and multiple cascading applications. MY9291
✦ Clock duty recovery for cascading application
✦ Schmitt trigger input
provides typical ±1.5% channel-to-channel LED
current accuracy. Additional features include a±0.1%
regulated output current capability and fast output transient
✦ Output Current Tr / Tf programmable
✦ -40°C to +85°C Ambient temperature range
response. MY9291 is available in a QFN20, SSOP20
and TSSOP20(Exposed Pad) package and specified over
the -40°C to +85°C ambient temperature range.
Applications
Order information
❑ Indoor and Outdoor LED Video Displays
❑ Full Color Mesh Display
Part
Package Information
MY9291SS SSOP20-150mil-0.635mm
2500 pcs/Reel
2500 pcs/Reel
3000 pcs/Reel
❑ Full Color Dot Matrix Module
TSSOP20-173mil-0.65mm
MY9291TE
❑ Architectural and Decorative Lighting
(Exposed Pad)
❑
LCD Display Backlighting
MY9291QD
QFN20-4mmx4mm
Typical Operating Circuits
Pin Configuration
VLED
Power
System
DI
DI
DO
DI
DO
Controller
MY9291
MY9291
DCK
DCKI
DCKO
DCKI
DCKO
1
n
Mar. 2010 Ver. 0.91
MY-Semi Inc.
0
For pricing, delivery, and ordering information, please contact MY-Semi Inc. at +886-3-658-5656,
or email to INFO@MY-Semi.com.tw or visit MY-Semi’s website at www.MY-Semi.com.tw