Specifications

7–16 EPSON
SED1234/35 Series
Low Power Consumption Mode
The SED1234, SED1235 Series is provided with the
standby mode and sleep mode with the object of low
power consumption when the unit is in the standby state.
● Sleep Mode
After the power circuit and oscillating circuit are turned
off by command and the power save command is ex-
ecuted, the sleep mode is set. This mode permits reducing
current consumption nearly to the static current value.
1. Liquid crystal display output
COM1 ~ COM28, COMS2, COMS3 : V
DD level
SEG1 ~ SEG60, SEGS2, SEGS6 : VDD level
2. DD RAM, CG RAM and symbol register
Written contents do not change and are stored re-
gardless of whether the sleep mode is turned on or
off.
3. In the operation mode, the status precedent to execu-
tion of the sleep mode is held. All the internal circuits
stops.
4. Power circuit and oscillating circuit
Turn off the built-in power supply and oscillating
circuit by power save command and power control
command.
Reset Circuit
When the RES input goes active, this LSI enters the
initialization status.
1. Display ON/OFF control
C = 0 : Cursor OFF
B = 0 : Blink OFF
DC = 0 : Double cursor OFF
D = 0 : Display OFF
2. Power save
O = 0 : Oscillating circuit OFF
PS = 0 : Power save OFF
3. Power control
VC = 0 : Voltage regulating circuit OFF
VF = 0 : Voltage follower OFF
P = 0 : Boosting circuit OFF
4. System set
CG = 0 : No use of CG RAM
As described in 6.1 MPU Interface, the RES pin is
connected to the MPU reset pin and performs initialization
concurrently with the MPU.
Regarding the reset signal, a pulse of at least 10 µs or
more active level must be input as described in 9. DC
Characteristics. Usually, the operation status is started in
1 µs from the edge of the RES signal.
In the SED 1230 Series where the built-in liquid crystal
power circuit is not used, the RES input must be active
when the external liquid crystal power supply is turned
on.