TLC5940_15 Datasheet, PDF (24/38 Pages) Texas Instruments – 16-Channel LED Driver

TLC5940
SLVS515D – DECEMBER 2004 – REVISED NOVEMBER 2015
www.ti.com
9.2.2 Detailed Design Procedure
9.2.2.1 Serial Data Transfer Rate
Figure 22 shows a cascading connection of n TLC5940 devices connected to a controller, building a basic
module of an LED display system. The maximum number of cascading TLC5940 devices depends on the
application system and is in the range of 40 devices. Equation 9 calculates the minimum frequency needed:
f(GSCLK) ₌ 4096 × f(update)
f(SCLK) ₌ 193 × f(update) × n
where
• f_(GSCLK): minimum frequency needed for GSCLK
• f_(SCLK): minimum frequency needed for SCLK and SIN
• f_(update): update rate of whole cascading system
• n: number cascaded of TLC5940 device
(9)
9.2.2.2 Grayscale (GS) Data
There are a total of 16 sets of 12-bit GS data for the PWM control of each output. Select the GS data of each
LED lamp and write the GS data to the register following the signal timing.
9.2.3 Application Curve
Figure 23. Output Waveform with Different Grayscale PWM Data
24
Submit Documentation Feedback
Product Folder Links: TLC5940
Copyright © 2004–2015, Texas Instruments Incorporated