TLC5947 Datasheet, PDF (1/25 Pages) Texas Instruments – 24-Channel, 12-Bit PWM LED Driver with

TLC5947
www.ti.com....................................................................................................................................................................................................... SBVS114 – JULY 2008
24-Channel, 12-Bit PWM LED Driver with
Internal Oscillator
FEATURES
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•23 24 Channels, Constant Current Sink Output
• 30-mA Capability (Constant Current Sink)
• 12-Bit (4096 Steps) PWM Grayscale Control
• LED Power-Supply Voltage up to 30 V
• V_CC = 3.0 V to 5.5 V
• Constant Current Accuracy:
– Channel-to-Channel = ±2% (typ)
– Device-to-Device = ±2% (typ)
• CMOS Logic Level I/O
• 30-MHz Data Transfer Rate (Standalone)
• 15-MHz Data Transfer Rate (Cascaded Devices,
SCLK Duty = 50%)
• Shift Out Data Changes With Falling Edge to
Avoid Data Shift Errors
• Auto Display Repeat
• 4-MHz Internal Oscillator
• Thermal Shutdown (TSD):
– Automatic shutdown at over temperature
conditions
– Restart under normal temperature
• Noise Reduction:
– 4-channel grouped delay to prevent inrush
current
• Operating Temperature: –40°C to +85°C
APPLICATIONS
• Static LED Displays
• Message Boards
• Amusement Illumination
• TV Backlighting
DESCRIPTION
The TLC5947 is a 24-channel, constant current sink
LED driver. Each channel is individually adjustable
with 4096 pulse-width modulated (PWM) steps. PWM
control is repeated automatically with the
programmed grayscale (GS) data. GS data are
written via a serial interface port. The current value of
all 24 channels is set by a single external resistor.
The TLC5947 has a thermal shutdown (TSD) function
that turns off all output drivers during an
over-temperature condition. All of the output drivers
automatically restart when the temperature returns to
normal conditions.
V_LED
V_LED
¼
¼
V_LED
V_LED
¼
Controller
DATA
SCLK
XLAT
BLANK
¼
¼
¼
¼
¼ _OUT0
OUT23
SIN
SOUT
SCLK
V_CC
XLAT TLC5947
IC1
BLANK
VCC
¼
¼
¼ _OUT0
OUT23
SIN
SOUT
SCLK
V_CC
XLAT TLC5947
BLANK ^ICn
VCC
R_IREF
IREF
GND
R_IREF
IREF
GND
3
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PowerPAD is a trademark of Texas Instruments, Inc.
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All other trademarks are the property of their respective owners.
3
UNLESS OTHERWISE NOTED this document contains
PRODUCTION DATA information current as of publication date.
Products conform to specifications per the terms of Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2008, Texas Instruments Incorporated