Display BANK B
Write GS to BANK A
Write GS to BANK B
Display BANK A
Write GS to BANK A
Display BANK B
Write GS to BANK B
Data Input
GCLK Signal
Normal Mode
Operating Mode
Normal Mode
Power-Save Mode
Power-Save Mode:
If all the GS data written during this period are 0, the
device enters the power-save mode at the falling edge
of the VSYNC command pulse on the LAT signal.
Any non-zero data written during this
period causes the device to begin
returning to the normal mode after
receiving the last WRTGS command
at the falling edge of LAT.
VSYNC
VSYNC
VSYNC
50 µs
Enter Power-Save
Mode Immediately
Start to Resume
Normal Mode
Fully
Recovered
t
SU
> 50 µs
Display BANK A
Frame N
Frame N
±
1
Frame N + 1
Frame N + 2
Function-Control Description
25
SLVUBF4A – February 2018 – Revised June 2019
Copyright © 2018–2019, Texas Instruments Incorporated
Function Control
TI Information — Selective Disclosure
The power-save mode (PSM) is enabled by setting PSM_EN to 1 in function-control register 2 (see FC2 in
). After power on, the default value of this bit is 0. When this function is enabled (PSM_EN = 1),
if all the grayscale (GS) data received for the next frame are 0, then the device enters power-save mode
at the moment the VSYNC command is input.
When operating in the power-save mode, the device continuously detects whether non-zero GS data is
input for the next frame. Among all the GS data for the next frame, if any non-zero data is detected, the
device resumes normal mode once finishing the whole GS input for the next frame.
shows the timing diagram of the power-save mode of operation.
Figure 2-19. Power-Save Mode
2.3.5 Thermal Shutdown (TSD)
The thermal shutdown (TSD) function turns off all device constant-current outputs when the junction
temperature (T
J
) exceeds 170°C (typical). It resumes normal operation when T
J
falls below 155°C (typical).
2.3.6 IREF Resistor Short Protection (ISP)
The IREF-resistor short-protection (ISP) function prevents unwanted large currents from flowing though
the constant-current output when the IREF resistor is shorted accidentally. The TLC694x device turns off
all output channels when the IREF pin voltage is lower than 0.19 V (typical). When the IREF pin voltage
goes higher than 0.325 V (typical), the TLC694x device resumes normal operation.