HD66108 Datasheet, PDF (37/60 Pages) Hitachi Semiconductor – (RAM-Provided 165-Channel LCD Driver for Liquid Crystal Dot Matrix Graphics)

HD66108
8. Standby Function
The HD66108T has a standby function providing low-power dissipation. Writing a 1 to bit 6 of the
address register starts up the standby function.
The LCD driving voltages, ranking from V1 to V6, must be set to V_CC to prevent DC voltage from being
applied to an LCD panel during standby state.
The HD66108T operates as follows in standby mode.
(1) Stops oscillation and external clock input
(2) Resets all registers to 0’s except the STBY bit
Here, note that the display memory will not preserve data if the standby function is turned on; the display
memory as well as registers must be set again after the standby function is terminated. V1 to V6
terminals must be connected to V_CC to prevent DC voltage being supplied during stand by.
Table 4 shows the standby status of pins and Table 5 shows the status of registers after standby function
termination.
Writing a 0 to bit 6 of the address register terminates the standby function. Writing values into the DISP
and Register No. bits at this time is ignored; these bits need to be set after the standby function has been
completely terminated.
Figure 23 shows the flow for start-up and termination of the standby function and related operations.
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