Datasheet

18
LTC1435A
TYPICAL APPLICATIONS
U
Constant-Current/Constant-Voltage High Efficiency Battery Charger
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
TG
BOOST
SW
V
IN

INTV
CC

BG
PGND
EXTV
CC
C
OSC
RUN/SS
I
TH

SFB
SGND
V
OSENSE

SENSE
–

SENSE
+

LTC1435A
1
2
3
4
8
7
6
5
AVG
PROG
V
CC

PIN
SENSE

I
OUT

GND
NIN
LT1620
C11
56pF
C9
100pF
D2
C14
1000pF
C10
100pF
C15
0.1µF
C6
0.33µF
C5
0.1µF
C13
0.033µF
E3
SHDN
R5
1k
C16
0.33µF
E4
I
PROG
*CONSULT CAPACITOR MANUFACTURER FOR RECOMMENDED 
ESR RATING FOR CONTINUOUS 4A OPERATION
E5
GND
C18
0.1µF
R6
10k
1%
R
PROG
C17
0.01µF
C12
0.1µF
C4
0.1µF
E3
GND
E1
V
IN
D1
C7
4.7µF
16V
+
L1
27µH
C3
22µF
35V
R1
0.025Ω
E6
BATT
Q1
Si4412DY
Q2
Si4412DY
E7
GND
C8
100pF
R2
1M
0.1%
R4
76.8k
0.1%
JP1B
1435A TA06
+
R3
105k
0.1%
JP1A
C2*
22µF
35V
R7
1.5M
C1*
22µF
35V
+ +
Efficiency
BATTERY CHARGE CURRENT (A)
0
EFFICIENCY (%)
90
95
100
4
1435A TA05
85
80
75
1
2
3
5
V
IN
= 24V
V
BATT
= 16V
V
BATT
= 12V
V
BATT
= 6V
Current Programming Equation
I
BATT
=
(I
PROG
)(R6) – 0.04
10(R1)