Datasheet

LTC3901
15
3901f
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 its circuits as described herein will not infringe on existing patent rights.
TYPICAL APPLICATIO S
U
240W 42V-56V Input to 12V at 20A Isolated 1/4 Brick (2.3" × 1.45")
5
46
A
B
12V
V
IN
15
LTC3723EGN-1
DRVB
SDRB
SDRA
COMP
CS
V
CC
UVLO
9
150k
1
0.47µF
1µF
DRVA
DPRG V
REF
SPRGGND SSFB C
T
330pF
22nF
100k
D8
10V
68nF
270pF
T2
1(1.5mH):0.5
T1
4T:6T(65µHMIN):6T:2T:2T
243k
2.49k
9.53k
10k
750Ω
1k
100Ω
1/4W
813
3
Si7370DP
×2
L4
1mH
C3
68µF
20V
V
F
•
•
3
2
8
19
5
4
16
10k
33k
200Ω
1/4W
R1
0.03Ω
1.5W
66.5k
RLEB
12
7
14
220pF
22nF
100Ω
665Ω
1k
866Ω
6.19k
1/4W
1.5nF
464k
30k
1/4W
SYNC PV
CC
CSF
+
V
F
LTC3901EGN
CSF
–
8
11 12
1
41013 7
1µF
4.7µF
3901 TA03
–V
OUT
V
OUT
–V
OUT
D7
10V
V
OUT
MF MF
GND PGND GND PGND TIMER
V
CC
470pF
22nF
14 15
1k
866Ω
42.2k
100Ω
MMBT3904
1k
6.19k
1/4W
CSE
+
V
E
–V
OUT
V
OUT
V
F
V
OUT
12V/20A
–V
OUT
CSE
–
65
ME ME
23 16
Si7370DP
×2
Si7852DPSi7852DP
L5
0.56µH
112
4
12V
D5
D6
3
5
1
6
•
••
•
•
9
7
V
E
+
0.1µF
1
6
5
4
B
2
A
D3
LTC4440ES6
BOOSTIN
+
TG
TSGND
V
CC
12V
3
0.1µF
Si7852DP Si7852DP
1
6
5
42
B
D4
LTC4440ES6
BOOSTIN
+
TG
TSGND
V
CC
12V
1µF
100V
×3
V
IN
V
IN
–V
IN
42V TO 56V
1µF
100V
C1, C2
47µF
16V
×2
+
1µF
1µF
100V
1µF, 100V TDK C3225X7R2A105M
C1, C2: SANYO 16TQC47M
C3: AVX TPSE686M020R0150
C4: MURATA GHM3045X7R222K-GC
D2: DIODES INC. ES1B
D3-D6: BAS21
D7, D8: MMBZ5240B
L4: COILCRAFT DO1608C-105
L5: COILCRAFT DO1813P-561HC
L6: PULSE PA1294.132 OR
PANASONIC ETQP1H1R0BFA
R1, R2: IRC LRC2512-R03G
T1: PULSE PA0805.004
T2: PULSE PA0785
6
10
I
SNS
I
SNS
0.1µF
11
58
1
2
1
MOC207
C4
2.2nF
250V
0.1µF
3
6
5
8
GND-F
V
+
GND-S
COLL REF
LT1431CS8
A
1.5k
22Ω
4.7Ω
4.7Ω
R2
0.03Ω
1.5W
V
F
D2
470pF
100V
L6
1.25µH
1k
1/4W
10Ω
1W
6
93
EFFICIENCY (%)
94
95
96
97
81012
LOAD CURRENT (A)
EFFICIENCY
14
16 18 20
42V
IN
48V
IN
56V
IN