
2
POWER SUPPLY
A-12
EPSON
S1C33L01 PRODUCT PART
2.3 Power Supply for I/O Interface (VDDE1)
The VDDE1 voltage is used for interfacing with external I/O signals. For the I/O interface of the S1C33L01, the
VDDE1 voltage is used as high level and the VSS voltage as low level.
Normally, supply the same voltage level as VDD. It can be supplied separately from VDD for 5 V interface. The VSS
pin is used for the ground common with VDD and VDDE2.
The following voltage is enabled for VDDE1:
VDDE1 = 1.8 V to 5.5 V (VSS = GND)
Notes: The S1C33L01 has 6 VDDE1 pins. Be sure to supply a voltage to all the pins. Do not open any of
them.
When VDDE1 = 5 V, the data bus inputs CMOS-interface-level signals, not TTL level.
When an external clock is input to the OSC1 or OSC3 pin, the clock signal level must be VDD.
The interface voltage level of the DSIO, P10, P11, P12, P13 and P14 pins is VDD.
2.4 Power Supply for LCD Interface (VDDE2)
The VDDE2 voltage is used for interfacing with LCD control signals. It can be supplied separately from VDD and
VDDE1. The VSS pin is used for the ground common with VDD and VDDE1.
The LCD controller pins/signals (pin No. 91 to 112) shown in Table 1.3.5, "List of Pins for LCD Controller
(SID13705)", except for the CLKI, CKSEL[2:0] and CNF3 pins use the VDDE2 voltage as their I/O interface level.
Note that the CLKI, CKSEL[2:0] and CNF3 pins use VDDE1 (power voltage for I/O interface).
The following voltage is enabled for VDDE2:
VDDE2 = 1.8 V to 5.5 V (VSS = GND)
Note: The S1C33L01 has 2 VDDE2 pins. Be sure to supply a voltage to all the pins. Do not open any of
them.
2.5 Power Supply for Analog Circuits (AVDDE)
The analog power supply pin (AVDDE) is provided separately from the VDD and VDDE1/2 pins in order that the
digital circuits do not affect the analog circuit (A/D converter). The AVDDE pin is used to supply an analog power
voltage and the VSS pin is used as the analog ground.
Supply the same voltage level as the VDDE1 to the AVDDE pin.
AVDDE = VDDE1, VSS = GND
Note: Be sure to supply VDDE1 to the AVDDE pin even if the analog circuit is not used.
Noise on the analog power lines decrease the A/D converting precision, so use a stabilized power supply and make
the board pattern with consideration given to that.