HM17CM256 HYNIX [Hynix Semiconductor], HM17CM256 Datasheet - Page 45

• Manufacturer Part Number: HM17CM256
• Description: 128XRGBX82 OUTPUT LCD DRIVER IC with built-in RAM
• Manufacturer: HYNIX [Hynix Semiconductor]

(31) SUPPLYING POWER AND ON/OFF SEQUENCE
(31-1) WHEN USING EXTERNAL POWER SUPPLY
(31-2) WHEN USING BUILT-IN POWER SUPPLY CIRCUIT
terminal when the logic VDD is floating can cause over-current and damage the IC
Special care should be taken to the next notice. Supplying the power at LCD driving voltage
power ON sequence
voltage at the terminals (V
V
then turn off the LCD driving voltage after logic power OFF.
voltage converting circuit is used) is recommended to prevent over-current.
voltage common port (V
circuit by command.
V
boosting voltage generation, the logic power at V
command.
during V
turn off the logic power at V
under LCD on voltage(LCD threshold voltage)level.
power OFF sequence
power ON sequence
power OFF sequence
DD
DD
Reset the IC after supplying the logic power at V
And when internal voltage converter is used, reset the IC after supplying the logic power at
Execute HALT command or reset the IC to turn off the outputs of LCD driving output port, and
Inserting series resistor of 50 ~100
This series resistor should be selected carefully because image quality can be dependent on.
Reset the IC after supplying the logic power at V
And when internal voltage converter is used, reset the IC after supplying the logic power at
You should turn on the display after the output level of internal power module is set.
If you do not keep this sequence, LCD can display wrong data.
To make off state of LCD driving output, cut the source to voltage common port (V
If V
Specially, when turn off the power, after cut the source to voltage common port (V
terminal, and then supply power to V
terminal, and then supply power to V
EE
, and V
DD
terminal voltage maintain voltage level specified in specification sheet.
DD
are supplied from different power source, V
EE
LCD
) of boosting voltage generation and then operate internal power
DD
, V
terminal after the voltage levels of V
1
, V
2
, V
3
, V
LCD
LCD
or fuse at V
4
).
terminal.
terminal.
DD
DD
terminal, and then turn on the LCD driving
DD
terminal or after supplying power through
LCD
terminal after reset the IC by HALT
or V
EE
OUT
terminal should be turned on/off
EE
terminal (when only internal
, V
OUT
HM17CM256
, V
LCD
, V
EE
1
~V
), and then
4
become
EE
- 45 -
) of