LX1571 Microsemi Corporation, LX1571 Datasheet - Page 12

• Manufacturer Part Number: LX1571
• Description: PHASE MODULATED AC SYNCHRONOUS SECONDARY-SIDE CONTROLLER
• Manufacturer: Microsemi Corporation

LX1570/1571
12
(17 to 20V)
Unless otherwise noted all resistors are 1/4W, 5%.
Note 1: For further information on PE53700 and PE64978 contact Pulse Engineering at 619-674-8100.
Note 2: A high value resistor must be coupled back to "COMP" pin to insure proper operation under light load conditions.
T2
V
V
f = 100kHz to 150kHz
P
IN
Core = RM4Z
N
N
(+)
(-)
P
S
=
=
Secondary
Transformer
Voltage
V
P
(10 to 30V)
25T #28AWG
25T #28AWG
0.047µF
C3
22µF
25V
C4
Note2
FIGURE 9 — THE LX1571 IN A 3.3V/10A SECONDARY-SIDE POWER SUPPLY APPLICATION
1M
IRLZ44
D8, 1N4937
300
0.56µF
P
Q1
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
HASE
1N4148
C6
R2, 2W
1
6
S.S.
M
D4
C
8
1
T
P
ODULATED
Look-ahead Switching
U1, LX1571
R E L I M I N A R Y
V
N
N
V
7
2
CC
FB
S
P
C1, 0.1µF
R4
COMP
OUT
DRV
3 . 3 V / 1 0 A S C H E M A T I C
C2
50V
6
3
3
4
AC S
0.1
GND
C7
47
C.S.
5
4
T2
C13
1µF
TM
YNCHRONOUS
C5
is a trademark of Linfinity Microelectronics Inc.
1000pF
MBR2545CT
Signal Gnd
100
C8
1/2 D1
R11
4
1
PE64978
(Note 1)
D6
1N5819
D5
1N5819
475
Pwr
Gnd
D
1%
R5
T1
S
ECONDARY
A T A
R9
3.3
1%
3
2
D7
1N4148
R8
SHORT
1/2 D1
MBR2545CT
S
PE53700
-S
(Note 1)
10µH
H E E T
IDE
L1
C
ONTROLLER
Note: Linfinity provides a complete and
C9
1500
µF
6.3V
tested evaluation board. For further
information contact factory.
C10
1500
µF
6.3V
C11
1500
µF
6.3V
C12
1500
µF
6.3V
R6
324
1%
R7
1k
1%
Copyright © 1997
Rev. 0.9.3
3.3V/10A
V
V
OUT (+)
OUT (-)
1/97