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
Internal Zener Diode
Low Cost Emitter Drive PWM Solution
0.13W Standby Power
Current Mode Operation
Short Circuit Protection
Over-Current Protection
Over-Temperature Protection
Under-Voltage Lockout with Auto-restart
Available in TO-94 Packages
RoHS Compliant and 100% Lead (Pb)-Free
Application
Battery Chargers
Universal Off-line Power Supplies
Power Adaptors
LED 3W-9W Lighting Solutions with SE1051
Pin Configuration
TO-94
TOP VIEW
ZENER
OUT
GND
Vcc
Pin Description
Name
VCC
GND
OUT
ZENER
Pin#
1
2
3
4
Function
The power supply of the IC, and is generally connected to opto-coupler's emitter
Supply ground
The output pin, connected to the emitter of NPN transistor.
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