Datasheet

11
LT1372/LT1377
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of circuits as described herein will not infringe on existing patent rights.
TYPICAL APPLICATIONS N
U
Low Ripple 5V to –3V “Cuk”
†
Converter
LT1372/LT1377
V
IN
S/S
GND
GND S
V
SW
NFB
V
C
5
4
7
6
8
3
1
+
+
R4
2k
R2
4.99k
1%
R1
1k
1%
C4
0.047µF
C6
0.1µF
V
OUT
–3V
250mA
LT1372 • TA05
V
IN
5V
C3
47µF
16V
C1
22µF
10V
C2
47µF
16V
C5
0.0047µF
••
41
3
L1*
2
D1**
SUMIDA CLS62-100L
MOTOROLA MBR0520LT3
PATENTS MAY APPLY
*
**
†
+
Dual Output Flyback Converter with Overvoltage ProtectionPositive-to-Negative Converter with Direct Feedback
LT1372/LT1377
V
IN
FB
V
C
V
IN
2.7V TO 13V
1
3
8
52
4
6, 7
*DALE LPE-4841-100MB [phone]
GND
NFB
LT1372 • TA04
V
SW
S/S
P6KE-20A
1N4148
MBRS140T3
MBRS140T3
C1
22µF
R2
1.21k
1%
R1
13k
1%
C2
0.047µF
C3
0.0047µF
R3
2k
R5
2.49k
1%
R4
12.1k
1%
–V
OUT
–15V
V
OUT
15V
C4
47µF
C5
47µF
ON
OFF
2, 3
6, 7
5
T1*
4
8
1
•
•
•
+
+
+
LT1372/LT1377
V
IN
V
C
V
IN
2.7V TO 16V
1
3
8
5
4
6, 7
*COILTRONICS CTX10-2 [phone]
GND
NFB
LT1372 • TA03
V
SW
S/S
D2
P6KE-15A
D3
1N4148
D1
MBRS130LT3
C1
22µF
C2
0.047µF
C3
0.0047µF
R1
2k
R3
2.49k
1%
R2
2.49k
1%
–V
OUT
†
–5V
C4
47µF
ON
OFF
V
IN
3V
5V
9V
I
OUT
0.3A
0.5A
0.75A
2
1
4
T1*
3
•
•
†
MAX I
OUT
+
+
D2
1N4148
Q2
1N5818
D1
1N4148
562Ω*
20k
DIMMING
10k
330Ω
10
12345
Q1
10µF
C1
0.1µF
V
IN
4.5V
TO 30V
V
IN
V
SW
V
FB
V
C
GND
S/S
5
84
2
16, 7
LT1372/LT1377
2µF
0.1µF
L1
33µH
T1
LT1372 • TA06
C1 = WIMA MKP-20
L1 = COILCRAFT DT3316-333
T1 = COILTRONICS CTX 110609
* = 1% FILM RESISTOR
DO NOT SUBSTITUTE COMPONENTS
Q1, Q2 = ZETEX ZTX849 OR ROHM 2SC5001
LAMP
C2
27pF
5mA MAX
2.2µF
2.7V TO
5.5V
22k
1N4148
OPTIONAL REMOTE
DIMMING
COILTRONICS [phone]
COILCRAFT [phone]
ON
OFF
CCFL BACKLIGHT APPLICATION CIRCUITS
CONTAINED IN THIS DATA SHEET ARE
COVERED BY U.S. PATENT NUMBER 5408162
AND OTHER PATENTS PENDING
+
+
+
90% Efficient CCFL Supply