AAT1236 Analogic Corporation, AAT1236 Datasheet - Page 2

• Manufacturer Part Number: AAT1236
• Manufacturer: Analogic Corporation

Pin Descriptions
Pin Configuration
2
Pin #
EP
10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
Symbol
AGND
RSET
GND
SDA
SCL
VIN
SW
LIN
OV
EN
B1
B2
A3
A2
A1
IN
Function
Input supply for the converter. Connect a 2.2µF or larger ceramic capacitor from VIN to GND.
Boost output over voltage detect pin. Use resistor divider to set the circuit's external over-
voltage protection. See Applications Information for details.
Enable pin.
Backlight current sink 1. Connect the cathode of the last LED in the string to B1.
Backlight current sink 2. Connect the cathode of the last LED in the string to B2.
LED current set resistor. A 22.6kΩ resistor from RSET to AGND sets the maximum LED cur-
rent in A1-A3 and B1-B2 to 20mA.
Input bias supply for the internal circuitry. Connect IN to VIN directly at the AAT1236.
Power ground for the boost converter. Connect GND to AGND at a single point as close to
the AAT1236 as practical.
Boost converter switching node. A 2.2µH inductor, connected between SW and LIN, sets the
boost converter's switching frequency.
I
I
Ground pin. Connect AGND to GND at a single point as close to the AAT1236 as practical.
Auxiliary current sink 3. Connect the cathode of the last LED in the string to A3.
Auxiliary current sink 2. Connect the cathode of the last LED in the string to A2.
Auxiliary current sink 1. Connect the cathode of the last LED in the string to A1.
Switched power input. Connect LIN to the external power inductor.
Exposed paddle (bottom). Connected internally to SW. Connect to SW or leave floating.
2
2
C interface serial data line.
C interface serial clock line.
RSET
GND
VIN
OV
EN
B1
B2
IN
1
2
3
4
5
6
7
8
TDFN34-16
(Top View)
High Efficiency White LED Drivers
16
15
14
13
12
10
11
9
LIN
A1
A2
A3
AGND
SCL
SDA
SW
for Backlight and Keypad
1236.2007.01.1.0