Triple-Output Charge Pump Regulator
General Description
The AAT2820 is a member of AnalogicTech's Total
Power Management IC™ (TPMIC™) product fam-
ily. It is a triple output charge pump targeted for
active matrix thin-film transistor (TFT), liquid crys-
tal displays (LCDs), and CCD camera bias for sys-
tems operating with lithium-ion/polymer batteries.
The device generates three regulated output volt-
ages for turn-on gate drive bias (V
POS
), turn-off
gate voltage bias (V
NEG
), and logic voltage.
The V
POS
and V
NEG
output voltages are independ-
ently regulated. Both outputs use external diode
and capacitor multiplier stages (as many stages as
required) to regulate output voltages up to +25V
and -25V. An additional regulated output voltage is
provided for biasing the display module. Built-in
soft-start circuitry prevents excessive inrush current
during start-up. A high switching frequency enables
the use of very small external capacitors. A low
shutdown feature disconnects the load from V
IN
and
reduces quiescent current to less than 0.1µA.
The AAT2820 is available in a Pb-free TDFN44-16
package and is specified over the -40°C to +85°C
operating temperature range.
AAT2820
Features
•
•
•
ChargePump
™
•
•
•
•
•
•
•
V
IN
Range: 2.7V to 5.5V
5V Regulated Output Voltage
Two Adjustable Regulated Output Voltages:
V
POS
and V
NEG
— Positive Charge Pump Up to +25V
— Negative Charge Pump Down to -25V
— Optional Power-Up Sequence with
AAT2820-1
Internal Power MOSFETs
<1µA of Shutdown Current
Internally Controlled Soft Start
Fast Transient Response
Ultra-Thin Solution (No Inductors)
16-Pin TDFN44 Package
Temperature Range: -40°C to +85°C
Applications
•
•
•
•
•
CCD Cameras
Hand-Held Instruments
Passive-Matrix Displays
Personal Digital Assistants (PDAs)
TFT Active-Matrix LCDs
Typical Application
C
FLY
C+
C-
EN
V
IN
C
IN
IN
Enable
Enable (Positive and
Negative Output)
V
OUT
C
OUT
EN/PN
DRVN
OUT
AAT2820
FBN
DRVP
V
NEG
REF
GND
FBP
V
POS
2820.2006.04.1.4
1
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
