LTC3900_1 Datasheet, PDF (16/20 Pages) Linear Technology – Synchronous Rectifier Driver for Forward Converters

LTC3900
typical applications
18V to 72V Input to 12V at 13A Active Reset Converter Fits in 1/8th Brick Size
V_IN
18V TO 72V
2.2µF
×3
PZTA42
33k
V_R2
10V
V_U1
1.5mH
40R2-4444.004
1_• 7
BAS516
6
10 ^HAT2169
V_IN
2_•
FG
HAT2173
×2
CG
PA2050.103
33µF
V_OUT
12V
13A
330µF
BAS516
57Ω
V_U1
1, 6
3
5
2, 4 ^LTC4440
HAT2173
×2
0.006Ω
5
33nF
Si2325
V_FB
22k
33k
BC857
174k
0.1µF
1µF
39.2K
13.3k
189k 332k
V_R2
V_B
220pF
GATE
0.1µF
237Ω
LT1952-1
1 _COMP
2 _{FB = 1.23V}
3 _ROSC
4 _SYNC
5 _MAXDC
S_OUT ¹⁶
V_IN ¹⁵
OUT ¹⁴
4.7µF
PGND ¹³
DELAY ^{12 137k}
6 _{VR = 2.5V}
7 _SD
8 _GND
OC ¹¹
I_SENSE ^{10 1k}
BLANK ⁹
22k
BAS516
V_U1
PS2801-1
V_FB
1.2k
10k
470R
BAS516
2.2nF
0.22µF
BAS521
680µH
1k
BCX55
1µF
7.5V
10k
10k
CG
22k
LTC3900
1 _CS+
8
SYNC
2 _CS–
7
TIMER
3
CG
6
GND
4
V_CC
5
FG FG
560R
470pF
LT4430
1
6
V_CC
2
OPTO
5 ^7.87k
GND COMP
3
OC
4
FB
1µF
47k
10nF
348k
V_OUT
18.2k
10pF
220pF
GATE
•
PE-68386
3900 TA05a
The High Efficiency of Converter is Achieved by Precise MOSFET Timing Provided
by LT1952 and LTC3900 Controllers.
96
94
92
90
88
86
84
82
24V_IN
48V_IN
80
0 2 4 6 8 10 12 14
I_OUT (A)
3900 TA05b
3900fb
16