Epson S1C17624 Technical Manual page 50

4 POWeR SuPPlY
D5 hVlD: V heavy load Protection Mode Bit
D1
Sets the internal logic voltage regulator into heavy load protection mode.
1 (R/W): Heavy load protection On
0 (R/W): Heavy load protection Off (default)
The internal logic voltage regulator enters heavy load protection mode by writing 1 to HVLD and it
ensures stable V
buzzer is driven with a port output (see Section 4.5). Current consumption increases in heavy load pro-
tection mode, therefore do not set if unnecessary.
D[4:1] Reserved
D0 VD1MD: Flash erase/Programming Mode Bit
Selects the V
D1
1 (R/W): V
D1
0 (R/W): V
D1
Normally set VD1MD to 0 (V
ming the Flash memory.
note: When the V
voltage is switched, the V
D1
programming should be started after the stabilization time has elapsed.
lCD Voltage Regulator Control Register (lCD_VReG)
Register name address Bit
lCD Voltage 0x50a3 D7–5 –
Regulator (8 bits)
D4
Control Register
D3–1 –
(lCD_VReG)
D0
D[7:5] Reserved
D4 lhVlD: lCD heavy load Protection Mode Bit
Sets the LCD system voltage regulator into heavy load protection mode.
1 (R/W): Heavy load protection On
0 (R/W): Heavy load protection Off (default)
The LCD system voltage regulator enters heavy load protection mode by writing 1 to LHVLD and it
ensures stable V
consistencies in density. Current consumption increases in heavy load protection mode, therefore do not
set if unnecessary.
D[3:1] Reserved
D0 VCSel: V Reference Voltage Select Bit
C
Selects the reference voltage for the LCD voltage booster/reducer according to the power supply
voltage V .
DD
1 (R/W): V
C2
0 (R/W): V
C1
As compared to the V
Set VCSEL to 0 when V
note: The V to V
C1
than 2.5 V.
4-4
output. Use the heavy load protection function when a heavy load such as a lamp or
D1
internal operating voltage value (operating mode).
= 2.5 V, Flash erase/programming mode
= 1.8 V, Normal operating mode (default)
= 1.8 V, default setting). It should be set to 1 before erasing/program-
D1
D1
name Function
reserved
lhVlD
LCD heavy load protection mode
reserved
VCSel V reference voltage select
C
–V outputs. Use the heavy load protection function when the LCD display has in-
C1 C3
is used as the reference voltage
is used as the reference voltage (default)
reference voltage, the V
C1
is less than 2.5 V.
DD
voltages cannot be obtained correctly if VCSEL is set to 1 when V
C3
Seiko epson Corporation
voltage requires 5 ms (max.) to stabilize. Flash memory
Setting
–
1 On 0 Off
–
1 V 0 V
C2
reference voltage is lower in current consumption.
C2
S1C17624/604/622/602/621 TeChniCal Manual
init. R/W Remarks
– – 0 when being read.
0 R/W
– – 0 when being read.
0 R/W
C1
DD
is less