Epson S1C17624 Technical Manual page 47

4 Power Supply
4.1 Power Supply Voltage (V
The operating voltage range of the S1C17624/604/622/602/621 is as follows:
For normal operation:
For Flash programming: V
S u p p l y a vo l t a g e w i t h i n t h e r a n g e t o t h e V
S1C17624/604/622/602/621 provides two or more V
be sure to connect them to + power source and GND.
4.2 analog Power Supply Voltage (aV
The analog power supply pin (AV
not affect the analog circuits (A/D converter). The AV
pin is used as the analog ground. The following voltage is enabled for AV
AV = V = 1.8 V to 3.6 V (V
DD DD
note: Be sure to supply the same voltage as V
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.
4.3 internal Power Supply Circuit
The S1C17624/604/622/602/621 has a built-in power supply circuit shown in Figure 4.3.1 to generate all the power
voltages required for the internal circuits. The power supply module consists of two circuits.
Oscillator and internal logic circuits Internal logic voltage regulator
LCD driver
AV
DD
V
DD
External
power
supply
V
D1
V
C1
V
C2
V
C3
CA
CB
V
SS
note: Be sure to avoid using the V
S1C17624/604/622/602/621 TeChniCal Manual
DD
V = 1.8 V to 3.6 V
DD
= 2.7 V to 3.6 V
DD
) is provided separately from the V
DD
= GND)
SS
DD
Table 4. 3.1 Power Supply Circuit
Circuit
LCD system voltage regulator
Internal logic
voltage regulator
LCD system
voltage regulator
Figure 4. 3.1 Configuration of Power Supply Circuit
and V –V
D1 C1
Seiko epson Corporation
)
p i n s w i t h t h e V
D D S S
and V pins. Do not leave any power supply pins open and
DD SS
)
DD
pin in order that the digital circuits do
DD
pin is used to supply an analog power voltage and the V
DD
:
DD
to the AV pin even if the analog circuit is not used.
DD
Power supply circuit
A/D converter
VD1MD
HVLD
V
D1
VCSEL
Internal circuit
LHVLD
V –V
C1 C3
pin outputs to drive external circuits.
C3
4 POWeR SuPPlY
p i n s a s t h e G N D l eve l . T h e
Output voltage
V
D1
V to V
C1 C3
AINx
OSC1, OSC2
Oscillator
OSC3, OSC4
COMx
LCD driver
SEGx
SS
4-1