
AT1314
Preliminary Product Information
High-Efficiency Step-Down
Current Regulator For LEDs
Feature
4.75V to 16V Supply Voltage Operating
Range.
600KHz 15% Fixed Switching Frequency.
Voltage-Mode PWM Step-Down Regulator.
Built-in Power MOSFET, Rds(on)
1A Output Current, Up to 91.9% Efficiency
0.4V 1.5% Internal Reference
Shutdown Current less than 20uA.
Thermal-Shutdown and Built-in Soft-Start.
Cycle-by-Cycle Current-Limit Protection.
Under-Voltage Lockout Protection.
Output Voltage Adjustable From 0.4V to 16V.
SOP-8 Package.
Application
Backlight for LCD Panels
Battery-Powered Backlight Applications
Cell Phones
PDAs
Other Handheld Devices with Dual Displays.
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879 WWW:
http://www.aimtron.com.tw
3/24/2006 REV:2.0 Email:
service@aimtron.com.tw
100m
.
Description
AT1314 is a voltage-mode PWM step-down
DC-DC converter capable of driving up to 1A
loads over a wide input supply range with excellent
line and load regulation characteristics. High
efficiency is obtained through the use of a low
Rds(on) P-channel power switch.
It uses a fixed switching frequency up to 600KHz
thus allowing smaller sized components. The
output voltage level is user-programmable via an
external resistive voltage divider. The built-in
soft-start can reduce inrush current on the input
source at turn on.
The device also has built-in cycle-by-cycle
current-limit, thermal shutdown, under-voltage
lockout and an ON/OFF logic-control that can
power down the regulator to a shutdown mode. In
shutdown mode the regulator draws less than 20uA
of supply current.
AT1314 is available in SOP-8 package.
Block Diagram
Current
Sense
OSC
600KHz
Contol
Logic
SW
IN
EN
GND
Regulator
Current Sense
Amplifier
PWM Comparator
P-MOS
-
+
0.4V
+
-
COMP
FB
Error
Amplifier
Soft-
Start
Aimtron reserves the right without notice to change this circuitry and specifications.