L7900
APPLICATION INFORMATION
Figure 1 :
Fixed Output Regulator.
Figure 2 :
Split Power Supply (± 15V/1A).
Notes :
1. To specify an output voltage, substitute voltage value for ”XX”.
2. Required for stability. For value given, capacitor must be solid
tantalum. If aluminium electrolitics are used, at least ten times
value should be selected. C
1
is required if regulator is located an
appreciable distance from power supply filter.
3. To improve transient response. If large capacitors are used, a
high current diode from input to output (1N4001 or similar) should
be introduced to protect the device from momentary input short
circuit.
Against potential latch-up problems.
Figure 3 :
Circuit for Increasing Output Voltage.
Figure 4 :
High Current Negative Regulator
(– 5V/4A with 5A current limiting).
V
O
=
V
XX
R
1
+
R
2
R
2
V
XX
>
3
I
d
R
2
C3 Optional for improved transient response and ripple rejection.
Figure 5 :
Typical ECL System Power Supply
(– 5.2V/4A).
Optional dropping resistor to reduce the power dissipated in the
boost transistor.
8/13
STMICROELECTRONICS [ STMICROELECTRONICS ]
