SE3901 Datasheet, PDF (1/8 Pages) Seaward Electronics Inc. – Low Power PWM Controller for OFF-LINE Battery Charger

Description
The SE3901 is a green-mode Pulse Width Modulation
(PWM) controller. It is specifically designed for low
power applications such as 5W-20W Adaptors and
Off-line battery Chargers. In these typical
applications, the low standby power, space saving,
and low cost are all required. SE3901 is a perfect
solutions to meet these challenges. The typical
standby power is only 0.13Watt.
In normal operation, the SE3901 switches on and off
at a fixed switching frequency of 60 kHz. With a
current limit capability of about 420mA, the SE3901
can directly drive the emitter of a high voltage NPN
transistor. When the output power falls below a given
level, the IC enters skip cycle mode to reduce power
consumption.
The SE3901 also features Under-Voltage Lockout ,
Over-Temperature Protection, Over-Current and
Short Circuit Protections.
The SE3901 is available in TO-94 Packages.
Features
¾ Internal Zener Diode
¾ Low Cost Emitter Drive PWM Solution
¾ 0.13W Standby Power
¾ Current Mode Operation
¾ Short Circuit Protection
¾ Over-Current Protection
¾ Over-Temperature Protection
¾ Under-Voltage Lockout with Auto-restart
¾ Available in TO-94 Packages
¾ RoHS Compliant and 100% Lead (Pb)-Free
Application
¾ Battery Chargers
¾ Universal Off-line Power Supplies
¾ Power Adaptors
¾ LED 3W-9W Lighting Solutions with SE1051
Pin Configuration
TO-94
TOP VIEW
ZENER
OUT
GND
Vcc
Pin Description
Name Pin# Function
VCC
1 The power supply of the IC, and is generally connected to opto-coupler's emitter
GND
2 Supply ground
OUT
3 The output pin, connected to the emitter of NPN transistor.
ZENER 4 The output pin, connected to Internal ZENER
Revision 1/20/2009
Preliminary and all contents are subject to change without prior notice.
© Seaward Electronics, Inc., 2008. • www.seawardinc.com • Page 1