Specifications

3–24 EPSON Rev. 1.1
S1D12205 Series
LED RAM (Register)
The S1D12205 Series has the LED drive functions to
drive the LCD by controlling the LE1 and LE2 pins.
The following provides the relationship between the
RAM address and write data by LED register setup.
The following defines the LE1 and LE2 pin state
depending on the TIM1, TIM2, LED1 and LED2 set
values.
Electronic Control RAM (Register)
The S1D12205 SERIES has the electronic control
functions to control LCD drive voltages and to adjust the
LCD display density. One of 32-state LCD voltages can
be selected when the 5-bit data is written in the Electronic
Control RAM.
The following provides the relationship between the
RAM address and write data by electronic control setup.
000
28H
29H
Electronic
Control
00 0 V
REG-0
V
REG-α
V
REG-2α
V
REG-29α
V
REG-30α
V
REG-31α
For test
00 001 1
00 010 2
11 101
11 110
11 111
29
30
31
Electronic Control Data
Status V
EV
D7 D0
RAM AddressFunction
* : Unused
α
: α=VREG/95 (1/4biased)
Note: Do not use address 29H as it can be used for IC chip test only.
***
***
***
***
***
***
*****
. . . . . . . . . . . . . . .
LED Register Set Value
TIM2 LED2
Output Status (LE1, LE2)
TIM1 LED1
0 0 LE = HIGH impedance
0 1 LE = LOW
1 0 Keeps LE LOW approximately 15 sec
after input of Display ON command.
1 1 LE = LOW
Note: When this function is used, minimize power supply and power
cable impedance to avoid IC misoperation due to large current.
LED Register Data
Function RAM Address
D7 D3 D2 D1 D0
LED ON/OFF 2AH ✽✽ ✽✽TIM2 TIM1 LED2 LED1
Timer
✽ : Unused