RH5RE Datasheet, PDF (18/20 Pages) RICOH electronics devices division – Supply Current Typ. 1.1uA (VOUT=3.0V, VIN=5.0V)

Rx5RE
TYPICAL APPLICATION
VIN
VIN
Rx5RE ^VOUT
VOUT
SERIES
C1 ⁺
+
C2
GND
GND
GND
In Rx5RE Series, a constant voltage can be obtained
without using capacitors C1 and C2. However, when the
wire connected to VIN is long, use capacitor C1. Output
noise can be reduced by using capacitor C2.
Insert capacitors C1 and C2 with the capacitance of
0.1µF to 2.0µF between input/output pins and GND pin
with minimum wiring.
APPLICATION CIRCUITS
• VOLTAGE BOOST CIRCUIT
VIN
VIN
+
C1
Rx5RE
SERIES
VOUT
GND
+
C2
ISS
R1
GND
VOUT
R2
The output voltage can be obtained by the follow-
ing formula :
VOUT=Vreg*¹Â· (1+R2/R1) + ISS · R2
Since the quiescent current of Rx5RE Series is so
small that the resistances of R1 and R2 can be set as
large as several hundreds kΩ and therefore the sup-
ply current of “Voltage Boost Circuit” itself can be
reduced.
Furthermore, since Rx5RE Series are operated by
a constant voltage, the supply current of “Voltage
Boost Circuit” is not substantially affected by the
input voltage.
*^{1) Vreg : Set Output Voltage of Rx5RE Series.}
• DUAL POWER SUPPLY CIRCUIT
IC1
VIN
VOUT
VIN
Rx5RE20A
+
C1
GND
ISS
IC2
VIN
+
C2
GND
Rx5RE30A
GND
VOUT
+
C3
VOUT1
5V
D
VOUT2
3V
R
GND
As shown in the circuit diagram, a dual power sup-
ply circuit can be constructed by using two Rx5RE
Series.
This circuit diagram shows a dual power supply
circuit with an output of 3V and an output of 5V.
When the minimum output current of IC2 is larger
than ISS of IC1, resistor R is unnecessary. Diode D is
a protection diode for the case where VOUT2
becomes larger than VOUT1.
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