lt3825 Linear Technology Corporation, lt3825 Datasheet - Page 28

• Manufacturer Part Number: lt3825
• Description: Isolated No-opto Synchronous Flyback Controller With Wide Input Supply Range
• Manufacturer: Linear Technology Corporation

LT3825
TYPICAL APPLICATIONS
28
36V TO 72V
V
IN
+
82
94
92
90
88
86
84
80
78
402k
2.2μF
100V
1
1%
36V
ALL CAPACITORS 25V UNLESS OTHERWISE NOTED
T1: EDFD25-3F3 GAP FOR L
Effi ciency vs Load Current
2
IN
15k
1%
29.4k
72V
1%
IN
3
LOAD CURRENT (A)
48V
3.01k
1%
PINS 10, 11, 12 TO PINS 7, 8, 9, 4T OF 5 MIL COPPER FOIL
IN
BAS21
4
20Ω
R7
12k
5
PGDLY
UVLO
FB
t
ON
100k
V
P
6
CC
SYNC
= 200μH (i.e., AL = 200nH/T
+
47k
1/4W
7
3825 TA02b
R
47μF
20V
CMP
PINS 1 TO 3, 32T OF 2 × 32AWG
PINS 4 TO 5, 11T OF 1 × 32AWG
PINS 1 TO 3, 32T OF 2 × 32AWG
PINS 1 TO 3, 32T OF 2 × 32AWG
2.1k
1%
8
ENDLY
PG
48V to 5V at 8A Isolated Supply
47pF
100k
LT3825
0.1μF
OSC
2
)
GND SFST
SG
SG
0.1μF
0.22μF
P6SMB100A
SENSE
SENSE
MBRS1100
C
CMP
V
C
Si4490DY
+
–
5.25
5.20
5.15
5.10
5.05
5.00
4.95
4.90
4.85
4.80
4.75
100k
680pF
10nF
Output Regulation vs Load Current
1
2
4
5
1
3
2 MIL
POLYESTER
FILM
0.03Ω
1W
•
•
PA0184
T1
3
SG
1nF
LOAD CURRENT (A)
1/4W
•
10Ω
330Ω
10
11
12
8
1
36V
7
8
9
0.1μF
•
4
IN
+
•
5
BAT54
4
48V
5
2.2nF
470μF
6TPE470MI
×4
IN
FMMT718 FMMT618
72V
3825 TA02a
6
IN
15Ω
Si7336ADP
×2
7
3825 TA02c
10k
8
0.1μF
2.2nF
250V
V
5V
8A
47Ω
OUT
B0540W
1μF
+
3525fa