Datasheet

LT3825
29
3825fe
TYPICAL APPLICATIONS
48V to 3.3V at 12A Isolated Supply
Efficiency vs Load Current Output Regulation vs Load Current
+
100k12k
3.01k
1%
28.7k
1%
402k
1%
20Ω
47Ω
47k
1/4W
BAS21
20Ω
•
•
•
•
100pF
250V
2.2nF
250V
C1 TO C4
47µF ×3
C5
470µF
L1
0.1µH
V
OUT
+
3.3V
12A
V
IN
+
36V TO 72V
T1
0.02Ω
1/2W
47µF
Si4490DY
Q1
Q2
15k
1%
750Ω 150k
10k
C1 TO C4: TDK C3225X5R0J476M
C5: SANYO 6TPD470M
L1: VISHAY IHLP2525CZERR10M
Q1: ZETEX FMMT618
Q2: ZETEX FMMT718
T1: PULSE PA1477NL
10k
BAT54
B0540W
15Ω
PA0184
330Ω
47pF
2.2µF
100V
0.1µF
0.01µF
1nF
10nF
2.2nF
0.1µF
3825 TA04a
1µF
t
ON
SYNC
PGDLY
UVLO
SENSE
–
V
C
SENSE
+
R
CMP
ENDLY OSC
LT3825
GND SFST
SG
FB
T1
V
CC
SG
SG
PG
C
CMP
Si7336ADP
•
LOAD CURRENT (A)
2
78
EFFICIENCY (%)
80
84
86
88
92
3
7
9
3825 TA04b
82
90
6
11
12
4
5
8 10
36V
IN
72V
IN
48V
IN
LOAD CURRENT (A)
3.13
OUTPUT (V)
3.23
3.33
3.43
3.18
3.28
3.38
4 6 8 10
3825 TA04c
122
36V
IN
72V
IN
48V
IN