Advanced Analog Technology, Inc.
May 2008
AAT1168/1168A/1168B
Product information presented is current as of publication date. Details are subject to change without notice.
TRIPLE-CHANNEL TFT LCD POWER SOLUTION
WITH OPERATIONAL AMPLIFIERS
FEATURES
ꢀ Built in 3A, 0.2Ω Switching NMOS
ꢀ Positive LDO Driver Up to 28V/5mA
ꢀ Negative LDO Driver Down to −14V/5mA
GENERAL DESCRIPTION
The AAT1168/AAT1168A/AAT1168B is a triple-channel
TFT LCD power solution that provides a step-up PWM
controller, two LDO drivers (one for positive high voltage
and one for negative voltage), five operational amplifiers,
and one high voltage switch up to 28V for TFT LCD
display.
ꢀ 1
V
and 4
V
Operational Amplifiers
COM
GAMMA
ꢀ 28V High Voltage Switch for VGH
ꢀ Internal Soft-Start Function
The PWM controller consists of an on-chip voltage
reference, oscillator, error amplifier, current sense circuit,
comparator, under-voltage lockout protection and
internal soft-start circuit. The thermal and power fault
protection prevents internal circuit being damaged by
excessive power.
ꢀ 1.2MHz Fixed Switching Frequency
ꢀ 3 Channels Fault and Thermal Protection
ꢀ Low Dissipation Current
ꢀ QFN-32 Package Available
The LDO drivers generate two regulated output voltage
set by external resistor dividers. VGH voltage does not
activate until DLY voltage exceeds 1.25V.
PIN CONFIGURATION
The AAT1168/AAT1168A/AAT1168B contains 4+1
operational amplifiers. VO1, VO2, VO4, and VO5 are for
VOUT3
EO
1
2
3
24
23
22
gamma corrections and VO3 is for
V
. In the short
COM
VREF
IN1
circuit condition, operational amplifiers are capable of
sourcing 100mA current for , and 200mA
current for
V
GND
VDD
GAMMA
AAT1168/
AAT1168A/
AAT1168B
V
.
COM
GND1
SW
4
5
6
7
21
20
19
18
17
With
the
minimal
external
components,
the
VO1
VI1-
VO5
VI5-
VI5+
VO4
AAT1168/A/B offers a simple and economical solution
for TFT LCD power.
VI1+
VO2
8
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Advanced Analog Technology, Inc. –
Version 1.00
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