Datasheet

LTC3766
52
3766fa
For more information www.linear.com/LTC3766
Figure 39. 36V-72V to 5V/15A Active Clamp Isolated Forward Converter
Typical applicaTions
FG
I
S
–
I
S
+
PT
+
FB
ITH
PT
–
SS
SW SG
GND PGND SGD FGD MODE
RUN V
IN
NDRV
LTC3766
V
CC
RUN
Si3437DV
(SOT23)
15mΩ
1/2W
3mΩ
2W
V
CC
IN
+
IN
–
FS/UVSSFLT
NDRV PG
R
CORE
DELAY SGND
14k
18.2k
L1: PULSE PA1392.152
T1: PULSE PA0810
T2: PULSE PA0297
15k26.1k
100Ω
100Ω
100Ω
33nF
NPO
22.1k 17.8k
3766 TA02
604Ω
4.42k
0.1µF
T2
2:1
T1
6:2
10.5k
15.0k
365k
I
PK
V
SEC
200k
Si3440DV
–V
IN
+V
IN
36V TO 72V
FDMS86201
BSC0901NS
••
SiR414DP
33nF
4.7µF
LTC3765
PGND
I
S
+
I
S
–
AG
1Ω
168Ω
I
SMAG
FS/SYNC V
S
+
V
S
–
330pF
1.0µF
2.2nF
250V
33nF
200V
47pF
220pF
470pF
2.2µF
100V
×3
220µF
6.3V
×2
L1
1.4µH
+V
OUT
5V
15A
–V
OUT
1nF
100V
10Ω
1/4W
1µF
10V
100nF
200V
•
•
Load StepEfficiency vs Load Current Pre-Biased Start-Up
LOAD CURRENT (A)
3
86
EFFICIENCY (%)
88
90
92
94
96
5
7 9 11
3766 F39b
13 15
V
IN
= 36V
V
IN
= 48V
V
IN
= 72V
V
OUT
1V/DIV
I
L1
5A/DIV
200µs/DIV
3766 F39c
V
IN
= 48V
V
PREBIAS
= 4.6V
V
OUT
200mV/DIV
I
OUT
5A/DIV
20µs/DIV
3766 F39d
V
IN
= 48V
V
OUT
= 5V
LOAD STEP = 5A TO 15A