TLC5916 Datasheet, PDF (1/30 Pages) Texas Instruments – 8-BIT CONSTANT-CURRENT LED SINK DRIVERS

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TLC5916, TLC5917
8-BIT CONSTANT-CURRENT LED SINK DRIVERS
SLVS695 – JUNE 2007
FEATURES
• Eight Constant-Current Output Channels
• Output Current Adjusted Through External
Resistor
• Constant Output Current Range:
5 mA to 120 mA
• Constant Output Current Invariant to Load
Voltage Change
• Open Load, Short Load and Overtemperature
Detection
• 256-Step Programmable Global Current Gain
• Excellent Output Current Accuracy:
– Between Channels: < ±3% (Max)
– Between ICs: < ±6% (Max)
• Fast Response of Output Current
• 30-MHz Clock Frequency
• Schmitt-Trigger Input
• 3.3-V or 5-V Supply Voltage
• Thermal Shutdown for Overtemperature
Protection
APPLICATIONS
• General LED Lighting Applications
• LED Display Systems
• LED Signage
• Automotive LED Lighting
• White Goods
• Gaming Machines/Entertainment
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, R_ext, 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 along with 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.
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.
PRODUCT PREVIEW information concerns products in the
formative or design phase of development. Characteristic data and
other specifications are design goals. Texas Instruments reserves
the right to change or discontinue these products without notice.
Copyright © 2007, Texas Instruments Incorporated