ST7628
6. PIN DESCRIPTION
6.1 POWER SUPPLY
Name
VDD
I/O
Description
Power supply for logic circuit (Digital VDD 1.65V~3.0V)
Power supply for Booster Circuit (Analog VDD 2.4V~3.3V)
Power supply for LCD. (Analog VDD 2.4V~3.3V)
Supply
Supply
Supply
Supply
Supply
Supply
Supply
Supply
Supply
VDD2
VDD3
VDD4
VDD5
VSS
Power supply for LCD. (Analog VDD 2.4V~3.3V)
Power supply for LCD. (Analog VDD 2.4V~3.3V)
Ground for logic circuit. Ground system should be connected together.
Ground for OSC circuit. Ground system should be connected together.
Ground for Booster Circuit. Ground system should be connected together.
Ground for LCD. Ground system should be connected together.
VSS1
VSS2
VSS4
6.2 LCD Power Supply Pins
Description
Name
I/O
Positive LCD driver supply voltages.
V0OUT
V0IN
V0S
V0OUT is the output voltage of V0 generated by ST7628.
V0IN is the input pin of power supply to generate V0 voltage for LCD.
V0S is the input pin of power supply to sense the V0 voltage.
V0OUT 、V0IN & V0S should be connected together.
I/O
Negative LCD driver supply voltages.
XV0OUT
XV0IN
XV0S
XV0OUT is the output voltage of XV0 generated by ST7628.
XV0IN is the input pin of power supply to generate XV0 voltage for LCD.
XV0S is the input pin of power supply to sense the XV0 voltage.
XV0OUT 、XV0IN & XV0S should be connected together.
I/O
Bias LCD driver supply voltages.
VgOUT is the output voltage of Vg generated by ST7628.
VgIN is the input pin of power supply to generate Vg voltage for LCD.
VgS is the input pin of power supply to sense the Vg voltage.
VgOUT 、VgIN & VgS should be connected together.
Vm is the I/O pin of LCD bias supply voltage
VgOUT
VgIN
VgS
Voltages should have the following relationship;
V0≧ Vg ≧ Vm ≧ VSS ≧ XV0
I/O
Vm
0.7V< Vm< VDDA-0.7V and 1.8V < Vg < 2xVDDA.
When the internal power circuit is active, these voltages are generated as following table according
to the state of LCD bias.
LCD bias
1/N bias
Vg
Vm
NOTE: N = 5 to 12
(2/N) x V0
(1/N) x V0
Ver 1.4
12/213
2008/08
SITRONIX [ SITRONIX TECHNOLOGY CO., LTD. ]
