LT1776C Linear Technology, LT1776C Datasheet - Page 20

• Manufacturer Part Number: LT1776C
• Description: Wide Input Range/ High Efficiency/ Step-Down Switching Regulator
• Manufacturer: Linear Technology

LT1776
RELATED PARTS
20
TYPICAL
PART NUMBER
LT1076
LTC
LT1374
LT1375/LT1376
LT1620
LT1676
LT1777
90
80
70
60
50
40
30
20
®
1149
10
V
10V TO 30V
IN
(SEE TEXT)
Battery Charger Efficiency —
= 12V
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] FAX: [phone] www.linear-tech.com
LT1121-5
Constant V
V
IN
LOAD CURRENT (mA)
V
APPLICATION
U3
IN
= 24V
DESCRIPTION
2A, 100kHz Step-Down Switching Regulator
High Efficiency Synchronous Step-Down Switching Regulator
4.5A, 500kHz Step-Down Switching Regulator
1.5A, 500kHz Step-Down Switching Regulators
Rail-to-Rail Current Sense Amplifier
Wide Input Range, High Efficiency, Step-Down Switching Regulator
Low Noise Buck Regulator
100
OUT
+
Region
C6
0.33 F
C1
39 F
63V
C5
100pF
1776 TA03
1000
1
6
U
C7
0.1 F
SHDN
SYNC
Wide V
LT1776
GND
V
U1
IN
1 F
R5
3k
R6
12k
5
4
C8
V
V
SW
+
V
20
FB
CC
90
80
70
60
50
40
30
IN
C
NC
0
Range, High Efficiency Battery Charger
7
2
3
8
8
7
1
Battery Charger Efficiency —
AVG
PROG
SENSE
1
C3
100pF
Constant I
V
LT1620
IN
GND
V
U2
OUTPUT VOLTAGE (V)
CC
= 12V
6
3
2
I
OUT
IN
IN
+
–
R3
22k
C4
2200pF
V
2
5
4
OUT
3
IN
= 24V
Region
4
D1
MBRS1100
5
COMMENTS
Operation Up to 45V Input (64V for HV Version)
Operation Up to 48V Input, 95% Efficiency, 100% Duty Cycle
Converts 12V to 3.3V at 2.5A in SO-8 Package
Operation Up to 25V Input, Synchronizable (LT1375)
Transforms Switching Regulators into High Efficiency
Battery Chargers
7.4V to 60V Input, 100kHz Operation, 700mA Internal Switch
Operation up to 48V, Controlled Voltage and Current
Slew Rates
100 H
1776 TA04
L1
6
0.5
R4
1776 TA02
7
6
5
4
3
2
1
0
0
+
Battery Charger Output Voltage
C1: PANASONIC HFQ
C2: AVX TPSD107M010R0080
L1: COILCRAFT DO3316P-104
LINEAR TECHNOLOGY CORPORATION 1998
C2
100 F
10V
50
1776f LT/TP 0499 4K • PRINTED IN USA
OUTPUT CURRENT (mA)
vs Output Current
100
R1
46.4k
1%
R2
12.1k
1%
150
BATTERY
200
1776 TA05
250