AT1308
Preliminary Product Information
Micro-Power Step up DC-DC Converter


2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
1 Rev A ; 01/18/05
LX
VBG
+
-FB
ON/OFF
Control
Logic
GND
Control Logic
EN
N
VBG
1.23V
VIN
+
-
Current Limit
400mA
Soft-Start
Thermal
Protection


Feature
•Operating Voltage:2.5V~6.0V
•High Operating Frequency: 1MHz
•Built-in N-MOS, R
ds(on)
≒ 0.3Ω (TYP)
•High Output Voltage: Up to 28V
•Shutdown Current <1µA
•Built-in Cycle-by-Cycle Current-limited.
•Built-in Soft-Start Function.
•1.5% 1.23V Reference.
•Tiny SOT-25 Package

Application
• STN/OLED Bias
• Personal Digital Assistants (PDAs)
• DSC

Description
The AT1308 step-up converter is designed for
small or medium size LCD panel of high bias
voltage with a constant current to provide PDAs,
and other hand-held devices. It features a fast 1.0
MHz current-mode PWM control with a built-in
0.3Ω N-MOS that allows for smaller capacitor and
inductor. Fault condition protection uses cycle-by-
cycle current limiting to sense maximum inductor
current and thermal protection. Also included
soft-start circuitry eliminates inrush current during
start-up. The AT1308 is available in 5-pin SOT-25
packages.

Block Diagram
Aimtron reserves the right without notice to change this circuitry and specifications.