AT1731A
Preliminary Product Information
DC-DC Power IC for TFT Panel
Feature
•
2.6V to 5.5V Supply Voltage Operating Range.
•
1.2MHz Fixed Switching Frequency.
•
Current-Mode PWM Step-Up Regulator
Description
The AT1731A DC-DC converter supply a compact
and small power supply solution to provide the
regulated voltages required by thin film transistor
Main High-Power Output up to 15V
(TFT) LCD display. A built-in power sequence
Typical
±
1% Accuracy
control.
Built-In N-MOS, R
ds(on)
≒0.25Ω(Typ.)
The main step-up DC-DC converter is a
Current-Limit Comparator
•
Negative Charge-Pump Output Voltage Down high-Frequency 1.2 MHz current-mode PWM
regulator with a built-in 0.25ΩN-MOS that allows the
to –30 V.
use of ultra-small inductors and ceramic capacitor to
•
Positive Charge-Pump Output Voltage Up to
generate an externally set output voltage up to 15V. It
30 V.
•
Internal Power-On Sequencing , Soft-Start.
provides fast transient response to pulsed loads while
•
Thermal Protection , Short Circuit Protection.
operating with efficiencies over 85%.
•
1uA Shutdown Current.
The two built-in charge-pump regulators are used to
•
1.5mA Quiescent Current.
generate the TFT gate-on and gate-off supplies and
•
16-pin TSSOP Package.
can adjust gate-on and gate-off output voltage with
external resistive divider between gate-off/on output
Application
voltage and ground.
•
TFT-LCD Notebook Display
•
TFT-LCD Desktop Monitor Panels.
AT1731A is available in TSSOP- 16 package.
•
Car Navigation Systems.
Block Diagram
/SHDN
REF
SCP
GND
Vin
V
DDN
SWN
FBN
Negative
Charge-Pump
Block
Reference
Voltage
Soft-
Start
Short-Circuit
Protection
Under-Voltage
Lockout
Thermal
Protection
Logic Control Block
Positive
Charge-Pump
Block
LX
V
DDP
SWP
FBP
Main Step-Up
Converter Block
PGND
FB
COMP
SS
Aimtron reserves the right without notice to change this circuitry and specifications.
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
2/8/2006 REV:1.1
Email:
service@aimtron.com.tw
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