Datasheet

16
LT1307/LT1307B
1307fa
Constant Current NiCd Battery Charger with Overvoltage Protection
for Acknowledge-Back Pagers
Step-Up/Step-Down Converter
Low Cost 2-Cell to 5V
V
IN
V
C
SW
FB
LT1307
L1
10µH
L1*
•
•
MBR0520
V
IN
2.1V TO 4.8V
100k
3
CELLS
608k
1.02M
3.3V
100mA
1000pF
L1: COILTRONICS CTX10-1 OR 2 MURATA ERIE LQH3C100
EFFICIENCY ≈70% TO 73%
1307 TA03
1µF
CERAMIC
2.2µF
CERAMIC
GND
SHDN
SHDN
10µF
CERAMIC
V
IN
V
C
SW
FB
LBO
LBI
LT1307
L1
10µH
V
IN
1.8V TO 1V
•
MBR0520L
47k
1 CELL
AA OR
AAA
2200pF
1µF
23
L1: COILTRONICS CTX10-1
1307 TA04
1nF
3V
200mV
15mA
–100mV
3 CELLS
NiCd
2.2µF
CERAMIC
GND
SHDN
1 = CHARGE
0 = SHUTDOWN
323k
280k 6.7Ω
1M
OVERVOLTAGE
PROTECTION
1µF
CERAMIC
1
4
30k
•
V
IN
SW
FB
LT1307
V
IN
1.4V TO 3.3V
L1
10µH
1N5818
SHDN
100k
323k
1M
5V
100mA
4700pF
C1, C2: PANASONIC ECA0JFQ221
(DIGI-KEY P5604-ND)
L1: SUMIDA CD43-100
1307 TA02
C1*
220µF
6.3V
0.1µF
GND
0.1µF
C2
220µF
6.3V
+
+
TYPICAL APPLICATIO S
U