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05. FUNCTIONAL DESCRIPTION
" Voltage converters (I) and (II)
Voltage converters (I) and (II) perform double boosting and triple boosting for input power voltage V
clocks generated in the CR oscillation circuit.
For double boosting, the double input voltage is obtained from the Vout pin by connecting an external pump-up
capacitor between CAP1+ and CAP1- and jumpering between CAP2+, CAP3+ and V
For triple boosting, 3V
CAP1+ and CAP1- and between CAP2+ and CAP2-, and connecting an external smoothing capacitor between
V
and V
.
DD
OUT
For quadruple boosting, 3V
between CAP1+ and CAP1- and between CAP2+ and CAP2-, and connecting an external smoothing capacitor
between V
and V
DD
OUT
Figures 5.3, 5.4 and 5.5 show the relationships between input and output voltages, using V
5V.
CAP1+=2V
=10V
DD
V
=5V
DD
V
=0V
SS
Fig.5.3 Relationships between
Double Boosting Voltages
Note 1: In triple boosting, the double boosting output (+10V) cannot be extracted from the CAP2+ pin.
Note 2: In quadruple boosting, the double boosting output (+10V) cannot be extracted from the CAP2+ pin.
Note 3: In quadruple boosting, the triple boosting output (+15V) cannot be extracted from the CAP3+ pin.
# Reference voltage generator, voltage stabilizer
The reference voltage generator generates a reference voltage required to operate the voltage stabilizer, and
provides a temperature gradient to the reference voltage.
There are three types of temperature gradients and the appropriate one is selected by a signal sent from the
temperature gradient selection circuit. The voltage stabilizer stabilizes boosting output voltage V
outputs any voltage.
As shown in Fig.5.5, the V
V
by connecting the external resistor R
OUT
V
SS
XP
OFF
RV
V
REG
The voltage stabilizer, which contains the power-off function, enables V
signal is sent from the system (microprocessor, etc.).
When XP
= High (V
OFF
If the V
output ON/OFF control is not necessary, XP
REG
lines).
6
is output from the V
DD
is output from the V
DD
.
CAP2+=3V
V
DD
V
SS
Fig.5.4 Relationships between
output voltage can be set to any voltage between the reference voltage V
REG
and changing the voltage of the intermediate tap.
RV
Control signal
R1
R
RV
Fig.5.6 Voltage Stabilizer
), the V
output is turned on; when XP
DD
REG
pin by connecting an external pump-up capacitor between
OUT
pin by connecting an external pump-up capacitor
OUT
=15V
DD
Note 1:
=5V
=0V
Triple Boosting Voltages
=100kΩ to 1MΩ
OFF
is fixed to High (V
OFF
EPSON
.
OUT
SS
CAP3+=4V
DD
V
=5V
DD
V
=0V
SS
Fig.5.5 Relationships
between Quadruple
Boosting Voltages
R
RV
= ──── $ V
V
RV
REG
R1
output ON/OFF control when the
REG
= Low (GND), it is turned off.
) as shown in Fig.4.5 (dashed
DD
S1F76640 Technical Manual (Rev.1.5)
using
DD
= 0V and V
=
DD
=20V
Note 3:
Note 2:
and
OUT
and
RV
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