lx1660 Microsemi Corporation, lx1660 Datasheet - Page 5

• Manufacturer Part Number: lx1660
• Description: Advanced Pwm Controller
• Manufacturer: Microsemi Corporation

Copyright © 1998
Rev. 1.1
NINV/SS
SYNCEN
HICCUP
SGND
PGND
BDRV
OT
TDRV
7/98
CS+
Pin
V
INV
CS-
EN
V
V
C
REF
CC
C1
ADJ
T
10
11
12
13
14
15
16
#
1
2
3
4
5
6
7
8
9
Description
A low voltage at this pin puts the IC in sleep-mode.
The purpose of this pin is to allow modulation of the OFF-time relative to the reference voltage. The OFF-time is
inversely proportional to the reference voltage. The inverting input of the upgrade voltage comparator is also
connected to this pin, when the voltage at this pin is below 0.7V, the controller shuts down.
This pin is the signal ground of the IC.
2V reference.
This pin is the inverting input of the error comparator.
This pin is the non-inverting input of the error comparator (LX1661 only: 40mV offset between this pin and error
comparator). This pin is pulled low during sleep-mode to allow soft-start function during start up.
A hiccup-mode capacitor connected to this pin adjusts duty cycle.
The OFF-time is programmed by connecting a capacitor from this pin to ground.
This is the inverting input of the pulse-by-pulse current comparator.
This is the non-inverting input of the pulse-by-pulse current comparator.
This pin enables the synchronous (bottom) driver. A high voltage at this pin disables the synchronous driver.
This is the IC supply voltage as well as the supply to the bottom MOSFET.
This is the gate drive to the bottom MOSFET
This is a separate ground for the top and bottom MOSFET.
This is the gate drive to the top MOSFET.
This pin is a separate power supply input for the top drive.
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
F U N C T I O N A L P I N D E S C R I P T I O N
P
A
R O D U C T I O N
D V A N C E D
P W M C
D
A T A
O N T R O L L E R
S
H E E T
LX1660/1661
5