This primary controller I.C., developed in BCD60II technology, has been designed to implement off BLOCK DIAGRAM
SYNC 1 RCT 2 TIMING 25V DC-LIM 15
MULTIPOWER BCD TECHNOLOGY
DIP16
SO16W
ORDERING NUMBERS: L4990/L4990A(DIP16) L4990D/L4990AD (SO16W)
line or DC-DC power supply applications using a fi
Features
as programmable soft start, IN/OUT synchronization, disable (to be used for over voltage protection and for power management), precise maximum Duty Cycle Control, 100ns (typ) leading edge blanking on current sense, pulse by pulse current limit and overcurrent protection with soft start intervention. VCC 8
VREF 4
3 DC 14 DIS 2.5V
+ + T DIS
Vref +
16V/10V
-
PWM UVLO 9 VC
13V.
The following content is an automatically extracted verbatim text
from the original manufacturer datasheet and is provided for reference purposes only.
View original datasheet text
®
L4990 L4990A
PRIMARY CONTROLLER
CURRENT-MODE CONTROL PWM SWITCHING FREQUENCY UP TO 1MHz LOW START-UP CURRENT < 0.45mA HIGH-CURRENT OUTPUT DRIVE SUITABLE FOR POWER MOSFET (1A) FULLY LATCHED PWM LOGIC WITH DOUBLE PULSE SUPPRESSION PROGRAMMABLE DUTY CYCLE 100% AND 50% MAXIMUM DUTY CYCLE LIMIT PROGRAMMABLE SOFT START PRIMARY OVERCURRENT FAULT DETECTION WITH RE-START DELAY PWM UVLO WITH HYSTERESIS IN/OUT SYNCHRONIZATION DISABLE LATCHED INTERNAL 100ns LEADING EDGE BLANKING OF CURRENT SENSE PACKAGE: DIP16 AND SO16W DESCRIPTION This primary controller I.C.
L4990A Datasheet
