Precision, Adjustable Shunt Regulator
(600mV Reference)
CAT102
FEATURES
Low voltage reference: 600mV
Low temperature coefficient reference: 25ppm
Accurate 600mV reference voltage:
+6mV at TJ = 25ºC
High PSRR: 45dB at 300kHz
High line rejection: ±1mV (VCC from 2.2V to 18V)
Low supply current: 300µA
Open collector output
Directly drives optocouplers
Compact 5-lead SOT23 package
Industrial temperature range: -40ºC to 85ºC
APPLICATION
SMPS control loop
Low temperature coefficient voltage reference
Power management
Replaces zener diodes
Isolated DC-to-DC converters
Network, telecom and cellular base station
Adjustable voltage reference
FUNCTIONAL DIAGRAM
1
FB
Error
Amplifier
VREF +
–
600mV
IN
5
+
–
OUT
3
2
GND
DESCRIPTION
The CAT102 is a low-voltage reference and amplifier.
Designed for the control loop of low-voltage power
supplies, the reference voltage has been designed for
600mV. Over a junction temperature from -40°C to
105°C the reference voltage is within 8mV of the
nominal 600mV. In addition, the error amplifier output
and the supply voltage pin are on separate pins.
Power supply rejection is a high 45dB at 300kHz. The
output, OUT, can sink 20mA at a maximum saturation
voltage of 250mV.
When combined with an optocoupler, the CAT102 can
be used as an error amplifier that controls the
feedback loop in isolated low-output voltage switching
power supplies.
For Ordering Information details, see page 8.
PIN CONFIGURATION
SOT-23 5L
Top View
FB 1 1
5 8 IN
GND 2 2
OUT 4 3
4 5 NC
PIN DESCRIPTION
Pin Name
FB
GND
OUT
NC
IN
Function
Inverting input to error amplifier
Ground
Output of error amplifier. Source & sink
current capability is 20mA.
No connection
Positive supply
© 2007 Catalyst Semiconductor, Inc.
1
Characteristics subject to change without notice
Doc. No. 4007 Rev. M