LP2950AC Advanced Monolithic Systems, LP2950AC Datasheet - Page 12

• Manufacturer Part Number: LP2950AC
• Description: 100mA LOW DROPOUT VOLTAGE REGULATOR
• Manufacturer: Advanced Monolithic Systems

TYPICAL APPLICATIONS
VOUT = 1.23V(1+R1/R2)
For 5V V
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone [phone] Fax [phone]
UNREGULATED
CURRENT
LIMIT SECTION
680
20k
2N3906
OUT
4.7M
, use internal resistors. Wire pin 6 to 7 and pin 2 to +V
INPUT
.033
220
3
2 Ampere Low Dropout Regulator
1A Regulator with 1.2V Dropout
SD
6
7
GND
V
+V
F
FB
4
TAP
LP2951
IN
+V
= V
IN
8
470
ERROR
LP2951
V
GND
OUT
IN
OUT
FB
1
8
4
+.5V
SENSE
k
5
OUT
7
(Continued)
2
1
10k
ERROR
FLAG
F
F
MJE2955
R
R
0.05
1%
2
1
+
k
TANT.
+V
SUPERTEX
VP12C
OUT
OUT
I
Q
+
Buss.
@ 2A
400 A
F
100 F
OUTPUT
5V ± 1% @
0 TO 1A
Operation: Reg.#1’s V
becomes active when V
Reg.#2 becomes active and via Q1 latches the main output off. When V
exceeds 5.7V Reg.#1 is back in regulation and the early warning signal rises,
unlatching Reg.#2 via D3.
Early warning flag on low input voltage
Main output latches off at lower input voltages
Battery backup on auxiliary output
2.7M
Q
1
Regulator with Early Warning and Auxiliary Output
RESET
6
7
3
6
7
470k
OUT
470k
V
V
FB
FB
SD
Latch Off When Error Flag Occurs
IN
+V
+V
TAP
+V
TAP
8
8
IN
IN
IN
is programmed one diode drop above 5V. It’s error flag
5.7V. When V
LP2951
LP2951
GND
GND
5
3
#1
#2
D
4
4
ERROR
SD
LP2950/LP2951
ERROR
SENSE
ERROR
4
SENSE
V
V
27 k
OUT
OUT
2
2
GND
+V
+V
LP2951
IN
IN
4
5
1
5
8
D
IN
1
D
V
3
drops below 5.3V, the error flag of
OUT
FB
330 k
MAIN 5V OUTPUT
1
7
+
+
1 F
EARLY WARNING
D
1 F
2
R
R
1
2
20
5V MEMORY
SUPPLY
3.6V
NICAD
+
RESET
V
V
DD
OUT
1 F
P
IN
again