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EPSON
S1C6F567 TECHNICAL MANUAL
CHAPTER 6: DIFFERENCES FROM MASK ROM MODELS
6.2 Power Supply
Since the S1C6F567 is produced using the Flash EEPROM process, the characteristics are different from
those of the mask ROM models.
Operating voltage range
S1C6F567:
2.7 to 5.5 V
S1C63557:
2.2 to 5.5 V
S1C63567:
2.2 to 5.5 V
The circuit blocks of the S1C6F567 except for the OSC1 oscillation circuit and LCD driver (CPU, ROM,
RAM and peripheral digital circuits) operate with the source voltage supplied between the VDD and
VSS terminals.
Power supply terminal for the Flash EEPROM (VDDF)
The S1C6F567 has a power supply (+) terminal exclusively for use with the Flash EEPROM block
(VDDF). In Serial Programming mode or Normal Operation mode, the VDDF terminal should be
connected to the VDD terminal so that the VDD voltage level is supplied to the VDDF terminal.
Power supply terminal for the OSC1 oscillation circuit (VD1)
The VD1 voltage that is generated by the internal voltage regulator is used only for the OSC1 oscilla-
tion circuit to stabilize the oscillation. In the S1C6F567, the VD1 voltage is fixed as follows:
VD1 output voltage = 1.85 V
± 0.3 V
Power supply for driving the LCD (VC1 to VC5)
The LCD system voltage circuit in the S1C6F567 generates the four voltages (for 1/4 bias): VC1, VC23,
VC4 and VC5. As similar to the S1C63557 and S1C63567, VC23 is generated by the internal voltage
regulator and the other voltages are generated by boosting and reducing it. Table 6.2.1 lists the voltage
values.
Table 6.2.1 LCD drive voltage
LCD drive voltage
VC1 (0.975 to 1.2 V)
VC23 (1.950 to 2.4 V)
VC4 (2.925 to 3.6 V)
VC5 (3.900 to 4.8 V)
1/2
× VC23
VC23 (standard)
3/2
× VC23
2
× VC23
VDD = 2.7 to 5.5V