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S1D13705 Hardware Functional Specification
X27A-A-001-10 Issue Date: 02/02/01
13 Power Save Modes
Two Power Save Modes have been incorporated into the S1D13705 to accommodate the
need for power reduction in the hand-held devices market. These modes are enabled as
follows:

13.1 Software Power Save Mode

Software Power Save Mode saves power by powering down the panel and stopping display
refresh accesses to the display buffer.

13.2 Hardware Power Save Mode

Hardware Power Save Mode saves power by powering down the panel, stopping accesses
to the display buffer and registers, and disabling the Host Bus Interface.
Table 13-1: Power Save Mode Selection
Hardware Power
Save Software Power
Save Bit 1 Software Power
Save Bit 0 Mode
Not Configured or 0 0 0 Software Power Save Mode
Not Configured or 0 0 1 reserved
Not Configured or 0 1 0 reserved
Not Configured or 0 1 1 Normal Operation
Configured and 1 X X Hardware Power Save Mode
Table 13-2: Software Power Save Mode Summary
Registers read/write accessible
Memory read/write accessible
Look-Up Table registers not accessible
LCD outputs are forced low
Table 13-3: Hardware Power Save Mode Summary
Host Interface not accessible
Memory read/write not accessible
Look-Up Table registers not accessible
LCD outputs are forced low