AAT1142
800mA Voltage-Scaling Step-Down Converter
Pin Descriptions
Pin #
TSOPJW-12
TDFN33-12
Symbol
Function
1
12
LX
Connect the output inductor to this pin. The switching node is
internally connected to the drain of both high- and low-side
MOSFETs.
2
3
11
10
PGND
Main power ground return pin. Connect to the output and
input capacitor return.
MODE/SYNC Connect to ground for PFM/PWM mode and optimized effi-
ciency throughout the load range. Connect to high for low
noise PWM Only operation under all operating conditions.
Connect to an external clock for synchronization (PWM Only).
4
5
6
9
8
7
SDA
SCL
EN/SET
I2C control pin: Data input.
I2C control pin: Clock input.
IC enable pin. Pull high to enable the AAT1142; pull low to
disable the AAT1142. Also serves as S2Cwire input for pro-
grammable output voltages.
7
6
FB
Feedback input pin. This pin is connected directly to the con-
verter output for programmable output.
Ground connection pin.
Input voltage for the converter.
Input voltage for the power switches.
Not connected.
8, 9, 10, 11
4, 5
3
1
2
EP
AGND
VIN
PVIN
N/C
121
121
n/a
n/a
Exposed paddle (bottom); connect to ground as closely as
possible to the device.
Pin Configuration
TSOPJW-12
(Top View)
TDFN33-12
(Top View)
1
2
3
4
5
6
12
11
10
9
LX
PGND
MODE/SYNC
SDA
SCL
VIN
1
2
3
4
5
6
12
11
10
9
PVIN
N/C
VIN
AGND
AGND
FB
LX
AGND
AGND
AGND
AGND
FB
PGND
MODE/SYNC
SDA
SCL
EN/SET
8
8
7
7
EN/SET
1. VIN and PVIN are tied together in the TSOPJW-12 package.
2
1142.2006.07.1.0
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
