TLC59208F Datasheet, PDF (18/27 Pages) Texas Instruments – 8-BIT FM+ I2C BUS LED DRIVER

TLC59208F
SCLS715 – MARCH 2009 .................................................................................................................................................................................................. www.ti.com
5. Once the correct two bytes (SWRST data byte 1 and byte 2 only) have been sent and correctly
acknowledged, the master sends a Stop command to end the SWRST Call. The TLC59208F then resets to
the default value (power-up value) and is ready to be addressed again within the specified bus free time
(t_BUF).
The I²C bus master may interpret a non-acknowledge from the TLC59208F (at any time) as a SWRST Call
Abort. The TLC59208F does not initiate a reset of its registers. This happens only when the format of the Start
Call sequence is not correct.
Individual Brightness Control With Group Dimming/Blinking
A 97 kHz fixed frequency signal with programmable duty cycle (8 bits, 256 steps) is used to control individually
the brightness for each LED.
On top of this signal, one of the following signals can be superimposed (this signal can be applied to the 4 LED
outputs):
• A lower 190 Hz fixed frequency signal with programmable duty cycle (8 bits, 256 steps) is used to provide a
global brightness control.
• A programmable frequency signal from 24 Hz to 1/10.73 s (8 bits, 256 steps) is used to provide a global
blinking control.
1 2 3 4 5 6 7 8 9 10 11 12
508 510 512 508 510 512
507 508 511 507 508 511 1 2 3 4 5 6 7 8 9 10 11
M X 256 X 2 X 40 ns
with M = (0 to 255)
(GRPPWM Register)
N X 40 ns with
N = (0 to 255)
(PWMx Register)
258 X 40 ns = 10.24 µs
(97.6 kHz)
Group Dimming Signal
12 3 4 5 6 7 8
256 X 2 X 256 X 40 ns = 5.24 ms (190.7 Hz)
12 3 4 5 6 7 8
Resulting Brightness + Group Dimming Signal
A. Minimum pulse width for LEDn brightness control is 40 ns.
B. Minimum pulse width for group dimming is 20.48 µs.
C. When M = 1 (GRPPWM register value), the resulting LEDn brightness control and group dimming signal will have two
pulses of the LED brightness control signal (pulse width = N × 40 ns,w ith N defined in the PWMx register).
D. The resulting brightness plus group dimming signal shown above demonstrate a resulting control signal with M = 4 (8
pulses).
Figure 8. Brightness + Group Dimming Signals
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