TLC5916, TLC5917
8-BIT CONSTANT-CURRENT LED SINK DRIVERS
www.ti.com
SLVS695A–JUNE 2007–REVISED MARCH 2008
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FEATURES
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Eight Constant-Current Output Channels
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30-MHz Clock Frequency
Schmitt-Trigger Input
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Output Current Adjusted Through External
Resistor
3.3-V or 5-V Supply Voltage
Constant Output Current Range:
5 mA to 120 mA
Thermal Shutdown for Overtemperature
Protection
Constant Output Current Invariant to Load
Voltage Change
APPLICATIONS
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General LED Lighting Applications
LED Display Systems
LED Signage
Automotive LED Lighting
White Goods
Open Load, Short Load and Overtemperature
Detection
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256-Step Programmable Global Current Gain
Excellent Output Current Accuracy:
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Between Channels: < ±3% (Max)
Between ICs: < ±6% (Max)
Gaming Machines/Entertainment
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Fast Response of Output Current
DESCRIPTION/ORDERING INFORMATION
The TLC5916/TLC5917 is designed for LED displays and LED lighting applications with constant-current control
and open-load, shorted-load, and overtemperature detection. The TLC5916/TLC5917 contains an 8-bit shift
register and data latches, which convert serial input data into parallel output format. At the output stage, eight
regulated current ports are designed to provide uniform and constant current for driving LEDs within a wide range
of VF variations. Used in system design for LED display applications, e.g., LED panels, it provides great flexibility
and device performance. Users can adjust the output current from 5 mA to 120 mA through an external resistor,
Rext, which gives flexibility in controlling the light intensity of LEDs. The devices are designed for up to 17 V at
the output port. The high clock frequency, 30 MHz, also satisfies the system requirements of high-volume data
transmission.
The TLC5916/TLC5917 provides a Special Mode in which two functions are included, Error Detection and
Current Gain Control. There are two operation modes and three phases: Normal Mode phase, Mode Switching
transition phase, and Special Mode phase. The signal on the multiple function pin OE(ED2) is monitored to
determine the mode. When an one-clock-wide pulse appears on OE(ED2), the device enters the Mode Switching
phase. At this time, the voltage level on LE(ED1) determines the mode to which the TLC5916/TLC5917 switches.
In the Normal Mode phase, the serial data can be transferred into TLC5916/TLC5917 via the pin SDI, shifted in
the shift register, and transferred out via the pin SDO. LE(ED1) can latch the serial data in the shift register to the
output latch. OE(ED2) enables the output drivers to sink current.
In the Special Mode phase, the low-voltage-level signal OE(ED2) can enable output channels and detect the
status of the output current, to determine if the driving current level is sufficient. The detected Error Status is
loaded into the 8-bit shift register and shifted out via the pin SDO, synchronous to the CLK signal. The system
controller can read the error status and determine whether or not the LEDs are properly lit.
In the Special Mode phase, the TLC5916/TLC5917 allows users to adjust the output current level by setting a
runtime-programmable Configuration Code. The code is sent into the TLC5916/TLC5917 via SDI. The positive
pulse of LE(ED1) latches the code in the shift register into a built-in 8-bit configuration latch, instead of the output
latch. The code affects the voltage at the terminal R-EXT and controls the output-current regulator. The output
current can be finely adjusted by a gain ranging from 1/12 to 127/128 in 256 steps. Therefore, the current skew
between ICs can be compensated within less than 1%. This feature is suitable for white balancing in LED color
display panels.
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright © 2007–2008, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.