Datasheet

µA723
PRECISION VOLTAGE REGULATORS
SLVS057D – AUGUST 1972 – REVISED JULY 1999
10
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
R2
V
I
15 pF
2N5004
1 kΩ
(see Note A)
R1
2N3997
1N4005
1 MΩ
100 µF
1 kΩ
220 Ω
0.1 µF
L = 1.2 mH
(see Note B)
REF
V
CC+
V
C
OUTPUT
V
Z
CURR LIM
CURR SENS
IN+
V
CC–
FREQ COMP
IN–
µA723
NOTES: A. The device requires a minimum of 9 V between V
CC+
and V
CC–
when V
O
is equal to or more positive than –9 V.
B. L is 40 turns of No. 20 enameled copper wire wound on Ferroxcube P36/22-3B7 potted core, or equivalent, with a 0.009-inch
air gap.
Regulated Output,
V
O
R3 =
3 kΩ
R4 =
3 kΩ
Figure 10. Negative Switching Regulator
1000 pF
V
I
2 kΩ
Input From
Series 54/74 Logic
2 kΩ
2N4422
R1
R2
REF
V
CC+
V
C
OUTPUT
V
Z
CURR LIM
CURR SENS
IN+
V
CC–
FREQ COMP
IN–
R
SC
µA723
NOTE A: A current-limiting transistor can be used for shutdown if current limiting is not required.
Regulated Output,
V
O
Figure 11. Remote Shutdown Regulator With Current Limiting