CAT102TDI-G ONSEMI [ON Semiconductor], CAT102TDI-G Datasheet - Page 4

• Manufacturer Part Number: CAT102TDI-G
• Description: Precision, Adjustable Shunt Regulator (600 mV Reference)
• Manufacturer: ONSEMI [ON Semiconductor]

CAT102
APPLICATIONS INFORMATION
The CAT102 adjustable shunt regulator features
isolated supply inputs and outputs, ideal for isolated
power-supply applications using an optocoupler in
the feedback path. The CAT102 sinks 20 mA with
V
the device to operate from 2.2 V to 18 V. The
CAT102 compares the FB input to a precision
600mV reference. If the FB input is low, the OUT pin
sinks no current. If FB rises above 600 mV, the OUT
pin sinks up to 20 mA.
Figure 1 shows the CAT102 configured as a shunt
regulator. To generate an output voltage of 0.6 V,
the FB pin has to be directly connected to the OUT
pin. A 1.0 µF capacitor from OUT to GND is
recommended when the output voltage is 0.6 V. A
resistor-divider connected from OUT to GND is used
to produce a higher output voltage as set by the
following equation:
Figure 1. Application circuits for 0.6 V output and 1.2 V output voltages
Doc. No. MD-4007 Rev. P
OUT
at 0.3 V. The wide input supply range allows
V
OUT
= (1 + R
3.3V
3.3V
V
V
IN
IN
1
/R
0.1µF
0.1µF
2
C
C
) x 0.6 V
1
1
5
2
5
2
IN
GND
IN
GND
CAT102
CAT102
OUT
OUT
R
R
FB
FB
3
3
3
1
3
1
4
The current limit can be adjusted by using a resistor R3
connected between the IN and OUT pins. For example,
a 3.3 V supply V
10 V supply works best with R
shunt regulator is limited to low-current applications with
the OUT pin capable of sinking up to 20 mA max.
10kΩ
10kΩ
R
R
1
2
C
1µF
2
C
1µF
2
V
0.6V/20mA
V
1.2V/20mA
OUT
OUT
IN
= (1 + R
is associated with R
1
/R
2
Characteristics subject to change without notice
) x 0.6V
3
= 470 Ω. The CAT102
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3
= 135 Ω, and a