TYPICAL APPLICATIONS (continued)
LP2950/LP2951
+ 6V
SEALED
LEAD-
120KΩ ..
1.5KΩ ..
ACID
BATTERY
SOURCE FB
AS385
1N457
FOR 5.5 V
400KΩ ..
100KΩ ..
3
SD
8
+VIN
LP2951
1
VOUT
SENSE
2
GND
4
MAIN V-
+
1uF
MEMORY V+
20KΩ ..
NI-CAD
BACKUP
BATTERY
Fig.4 Low Battery Disconnect
39kΩ ..
RESET
8
5 __+_V_I_N_
ERROR
2
SENSE
1
V OUT
-
LP2951
3
C4
SD
7
+
FB
39kΩ ..
GND
TAP
4
6
+VOUT = 5V
+ 1uF
1%
6V
LEAD-
ACID
1%
BATTERY
100kΩ ..
-
C1
+
1kΩ ..
-
C2
+
1% 1kΩ ..
-
C3
+
10kΩ ..
R3
1% 20kΩ ..
100kΩ ..
100kΩ ..
<5.8V**
100kΩ ..
<6.0V**
<6.2V**
* OPTIONAL LATCH OFF WHEN DROPOUT OCCURS. ADJUST R3 FOR C2 SWITCHING WHEN
VIN IS 6.0V
* OUTPUTS GO LOW WHEN V IN DROPS BELOW DESGNATED THRESHHOLDS
Fig. 5 Regulator with State-of-Charge Indicator
Rev. 11/2/00