PRODUCT DATASHEET
AAT3192
ChargePump
TM
2-Channel Charge-Pump LED Driver
Pin Descriptions
Pin
1
2
3
4
5
Symbol
N/C
OUT
C-
C+
IN
EN/SET
(AAT3192-1/-2/-3)
Description
No connection.
Charge pump output. OUT is the output of the charge pump. Bypass OUT to GND with a 1μF or
larger ceramic capacitor.
Charge pump capacitor negative node.
Charge pump capacitor positive node. Connect a 1μF ceramic capacitor between C+ and C-.
Power source input. Connect IN to the power source, typically the battery. Bypass IN to GND with a
1μF or larger ceramic capacitor.
LED enable and serial control input. EN/SET is the ON/OFF control for the LED and the S
2
Cwire digi-
tal input for the AAT3192-1/-2/-3 to control serially the LED brightness according to the maximum
current set by R
SET
.
LED ON/OFF and PWM control input. This logic input controls the LED outputs for the AAT3192-4.
Alternatively, a PWM signal from a GPIO or an equivalent signal from a separate controller can be
used to control LED output current linearly. A PWM signal, ranging from 10% to 100% duty cycle,
controls the LED current linearly between ZS and FS.
A 1% tolerance resistor from this pin to GND sets the maximum LED current level. For optimal LED
output current accuracy and matching in the AAT3192-1/-2/-4, a 14.3kΩ resistor sets each full-scale
output current to 20mA, maximum. For the AAT3192-3, a 11.5kΩ resistor is recommended.
Ground. Connect this pin to the system’s ground plane.
LED2 Current Sink Input. D2 is the input of LED2 current sink. Connect LED2’s anode to OUT and
its cathode to D2.
LED1 Current Sink Input. D1 is the input of LED1 current sink. Connect LED1’s anode to OUT and
its cathode to D1.
6
EN/PWM
(AAT3192-4)
7
8
9
10
RSET
GND
D2
D1
Pin Configuration
SC70JW-10
(Top View)
N/C
OUT
C-
C+
IN
1
2
3
4
5
10
9
8
7
6
D1
D2
GND
RSET
EN/SET
2
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3192.2008.07.1.3
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