Datasheet

21
LTC1698
1698f
TYPICAL APPLICATIO S
U
V
CC
14
2 1
5
1µF
25V
82pF
OVLO SHDN
1.24k
1%
73.2k
1%
24k
10k
270k
0.25W
68µF 25V
1000pF
56k
5V
REF
6
F
SET
4700pF
8
SS
10 13
BAT54
BAT54
T2
MIDCOM, INC
31264R
BAS21LT1
BAS21LT1
BAT54
ZVN3310F
9
V
C
PGND
12
I
MAX
V
FB
37 4
THERM
LT3781
SYNC SGND
52.3k
1%
10Ω
1k
3k
1k
3.3k
20k 0.25W
100Ω
0.25W
FZT603 ZETEX
4.7µF
16V
0.22µF
50V
1
10k
5V
REF
ISO1
MOC207
7
143
3 1
4 6
5
14
15
6 5
8
2
3300pF
4700pF
47Ω
0.01µF
50V
5V
REF
15
SG
+
11
SENSE
16
BG
18
BSTREF
19
TG
17 20
BAS21LT1
0.1µF
100V
1mH
DO1608C-105
COILCRAFT
BLKSENS
V
BST
220pF
1.5µF
100V
4.7µH
DO1608C-472
COILCRAFT
0.022µF
1000pF
•
•
SYNC V
FB
OVPIN
MARGIN
I
COMP
V
DD
OPTODRV
V
AUX
0.1µF
50V
0.1µF
50V
16
I
SNS
I
SNSGND
FG
2
CG
PGND GND
LTC1698
PWRGD
6
8 9 7 13
909Ω
0.1%
8.25k 0.1%
3411 1012
V
COMP
1698 F13
1k
0.01µF
MURS120T3
0.025Ω
1/2W
3 6
7
5 4
SUD40N10-25
SUD40N10-25
SUD40N10-25
470pF
100V
470pF
100V
2200pF
250V
MURS120T3
MURS120T3
10Ω
1
8
11 12 10
9
•
••
2
T1
EFD25
10Ω
V
IN
+
V
IN
–
1.5µF
100V
1.5µF
100V
V
OUT
+
V
OUT
–
68µF 25V AVX
68µF 25V AVX
68µF 25V AVX
68µF 25V AVX
22Ω
0.25W
22Ω
0.25W
25µH
MAG INC CORE
55380-A2 18T #18AWG
330pF
+
+
+
+
V
TOP
3.3Ω
V
IN
V
CC
V
IN
V
CC
V
TOP
V
TOP
V
OUT
–
V
OUT
+
V
CC
15V
MMBZ5245BLT1
20k
0.1µF
50V
0.33µF
50V
V
OUT
+
BAT54
10Ω 0.25W
10V MMBZ5240BLT1
10k
1k
UNLESS NOTED: ALL PNPs MMBT39O6LT1
NC
0.015Ω
100pF
200Ω
18V MMBZ5248BLT1
110Ω
0.1µF
T1 EFD25-3F3
LP = 120µH
2mil GAP EACH LEG
2M POLYESTER FILM
SQUARE 0.031 INCH
MARGIN TAPE
PINS 9-10 5T BIFILAR 33AWG PINS 2-5 12T BIFILAR 33AWG PINS 4-3 7T QUADFILAR 26AWG PINS 7,8-11,12 12T BIFILAR 24AWG PINS 6-4 8T QUADFILAR 26AWG
Si4486EY ×2
Si4486EY ×2
•
215Ω215Ω
0.033µF
Figure 13. 36V
IN
-72V
IN
to 12V/5A Isolated Synchronous Forward Converter