Epson Research and Development
Page 17
Vancouver Design Center
S5U13704B00C Rev. 1.0 ISA Bus Evaluation Board User Manual
S1D13704
Issue Date: 01/02/12
X26A-G-005-03
6.10 Power Save Modes
The S1D13704 supports one hardware and one software power save mode. These modes
are controlled by the utility 13704PWR. The hardware power save mode needs to be
enabled by 13704PWR and then activated by DIP switch SW1-6. See Table 2-1: “Config-
uration DIP Switch Settings,” on page 8 for details on setting this switch.
6.11 Adjustable LCD Panel Negative Power Supply
Most monochrome passive LCD panels require a negative power supply to provide
between -18V and -23V (I
out
=45mA). For ease of implementation, such a power supply has
been provided as an integral part of this design. The VLCD power supply can be adjusted
by R21 to give an output voltage from -14V to -23V, and is enabled/disabled by the
S1D13704 control signal LCDPWR.
LCDPWR is an S1D13704 output signal which is configurable as active high or active low
by the CNF4 signal status on the rising edge of the RESET# signal. For the proper operation
of the VLCD power supply, LCDPWR must be configured as active low.
Determine the panel’s specific power requirements and set the potentiometer accordingly
before connecting the panel.
6.12 Adjustable LCD Panel Positive Power Supply
Most color passive LCD panels and most single monochrome 640x480 passive LCD panels
require a positive power supply to provide b23V and +40V (I
out
=45mA). For ease
of implementation, such a power supply has been provided as an integral part of this design.
The V
DDH
power supply can be adjusted by R15 to provide an output voltage from +23V
to +40V and is enabled/disabled by the S1D13704 control signal LCDPWR.
LCDPWR is an S1D13704 output signal which is configurable as active high or active low
by the CNF4 signal status on the rising edge of the RESET# signal. For the proper operation
of the VDDH power supply, LCDPWR must be configured as active low.
Determine the panel’s specific power requirements and set the potentiometer accordingly
before connecting the panel.
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