RE5RE57AC-RF RICOH electronics devices division, RE5RE57AC-RF Datasheet - Page 20

• Manufacturer Part Number: RE5RE57AC-RF
• Description: VOLTAGE REGULATOR FOR MIDDLE OUTPUT CURRENT
• Manufacturer: RICOH electronics devices division

• CURRENT BOOST CIRCUIT
• CURRENT BOOST CIRCUIT WITH OVERCURRENT LIMIT CIRCUIT
• CURRENT SOURCE
GND
V
IN
GND
V
V
IN
IN
C1
C1
+
R1
+
Tr.2
+
V
IN
Tr.1
R2
SERIES
Vbe2
R 5RE
V
IN
GND
Tr.1
SERIES
R 5RE
V
V
OUT
IN
GND
I
SS
SERIES
R 5RE
R
V
OUT
GND
+
C2
I
OUT
V
OUT
GND
V
+
OUT
C2
I
V
GND
OUT
OUT
by the current boost circuit constructed as shown in
this circuit diagram.
caused by output short-circuit or overcurrent is shown in
this circuit diagram.
I
additionally providing the current boost circuit with Tr.2
and R2, Tr.2 is turned ON and the base current of Tr.1 is
increased, so that the output current is limited.
as follows :
this circuit diagram can be used. Output Current
I
Take care that Output Current I
its allowable current.
OUT
OUT
*
A circuit for protecting Tr.1 from the destruction
When the voltage reduction caused by the current (
Current limit of Overcurrent Limit Circuit is obtained
Output current of 120mA or more can be obtained
A current source with the structure as shown in
1) Vreg : Set Output Voltage of R 5RE Series.
) which flows through R2 reaches Vbe2 of Tr.2 by
I
is obtained as follows :
OUT
I
OUT
=Vreg /R + I
Vbe2/R2
*
1
SS
OUT
does not exceed
R 5RE
aa
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