HD66740 Datasheet, PDF (71/95 Pages) Hitachi Semiconductor – 112 x 80-dot Graphics LCD Controller/Driver

HD66740
Standby Mode
Setting the standby mode bit (STB) to 1 puts the HD66740 in the standby mode, where the device stops
completely, halting all internal operations including the R-C oscillation circuit, thus further reducing
current consumption compared to that in the sleep mode. Specifically, character and segment displays,
which are controlled by the multiplexing drive method, are completely halted. Here, all the SEG (SEG1
to SEG112) and COM (COM1 to COM80) pins output the GND level, resulting in no display. If the
AMP bit is set to 0 in the standby mode, the LCD drive power supply can be turned off.
During the standby mode, no instructions can be accepted other than the start-oscillation. To cancel the
standby mode, issue the start-oscillation instruction to stabilize R-C oscillation before setting the STB bit
to 0.
Turn off the LCD power supply: AMP = 0
Set standby mode: STB = 1
Standby mode
Issue the start-oscillation instruction
Wait at least 10 ms
Cancel standby mode: STB = 0
Turn on the LCD drive power supply: AMP = 1
Figure 40 Procedure for Setting and Canceling Standby Mode
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