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KA78RH33
Semi Low Dropout Voltage Regulator
Features
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Fixed Output Voltage of +3.3V
Space Saving SMD types of DPAK
1V(Typ) Dropout at Io=800mA
Output Current of 800mA
Thermal Shutdown Protection
Over Current Protection
Output trimmed to +/-1% Tolerance
No minimum Load Requirement
Description
The KA78RH33 is a +3.3V fixed Low Dropout Voltage
Regulator specifically designed for use in low voltage oper-
ation. The maximum load current is 0.8A and the dropout
voltage is guaranteed to be 1V(Typ). The Dropout Voltage
varies with load current. The regulator consists of compos-
ite PNP-NPN pass transistors.
D-PAK
1
1. GND 2. Vout 3.Vin
Internal Block Diagram
3.Vin
CURRENT
GENERATOR
PROTECTION
CIRCUIT
2.Vout
1.GND
Rev. 1.0.1
©2001 Fairchild Semiconductor Corporation
KA78RH33
Absolute Maximum Ratings
Parameter
Power Supply Input Voltage
Output Load Current
Junction Temperature
Operating Junction Temperature
Storage Temperature
Symbol
Vin
Io
Tj
Topr
Tstg
Value
15
800
150
-25 ~ 125
-55 ~ 150
Unit
V
mA
°C
°C
°C
Temperature Characteristics
Parameter
Temperature Coefficient of Output Voltage
Symbol
△
Vo/
△
T
Value
+ / -0.02
Unit
% /
°C
Electrical Characteristics
(Refer to the test circuit. Vin= 5V, Co=10uF, Ta = 25°C, unless otherwise specified.)
Parameter
Output Voltage
Output Voltage
Line Regulation
Load Regulation
Ripple Rejection
Dropout Voltage
Quiescent Current
Temperature Coefficient of
Output Voltage
Peak Output Current
Output Noise Voltage
Symbol
Vout
Vout
Rline
Rload
RR
Vdrop
Iq
△
Vo/
△
T
Ipk
Vn
Conditions
Io=10mA, Tj=25°C
Vin = 4.8V to 12V
Io = 10mA to 800mA
Tj = -25°C to 125°C
Vin=4.8V to 12V, Io=10mA
Io = 10mA to 800mA
f=120Hz, Io=500mA
Vin = 6.3 +/- 1Vrms
Io = 100mA
Io = 500mA
Io = 800mA
Vin <= 12V
Tj = -25°C to 125°C
Io = 10mA
Vin = 6.3V
f = 10Hz to 10KHz
Min.
3.27
3.23
-
-
55
-
-
-
-
-
800
-
Typ.
3.3
3.3
1
1
-
1
1.05
1.1
5
0.2
-
100
Max.
3.33
3.37
10
20
-
1.2
1.25
1.4
10
-
-
-
Unit
V
V
mV
mV
dB
V
mA
mV/°C
mA
µVrms
2