Datasheet

9
LT1072
1072fc
Totally Isolated Converter
Synchronizing with Bipolar Transistor Synchronizing with MOS Transistor
FROM 5V
LOGIC
R1
3k
R2
2.2k
C2
68pF
V
IN
V
C
GND
LT1072
2N2369
R3
C1
LT1072 • OP01
FROM 5V
LOGIC
*SILICONIX OR EQUIVALENT
R2
2.2k
D2
1N4158
C2
200pF
D1
1N4158
V
IN
V
C
GND
LT1072
R3
C1
VN2222*
LT1072 • OP02
LT1072 OPERATIO
U
C5
25µF*
R4
2.7k
C3
0.47µF
C2
0.01µF
1:N
D1
COM
15V
L1
10µH
OPTIONAL
OUTPUT FILTER
N
N
V
IN
5V
500Ω
R2
*REQUIRED IF INPUT LEADS ≥ 2”
N = 0.875 = 7:8
FOR V
OUT
= 15V
5k
C1
200µF
C5
200µF
C6
200µF
C4
200µF
–15V
L2
10µH
V
IN
V
SW
FB
V
C
GND
LT1072
SWITCH VOLTAGE
V
OUT
+ V
f
(V
f
= DIODE FORWARD VOLTAGE)
t
OFF
t
ON
V
IN
0
0V
SECONDARY VOLTAGE
N • V
IN
≈ 16V
LT1072 • TA03
+
+
+
+
+
TYPICAL APPLICATIO S
U