AAT2860 Datasheet, PDF (2/23 Pages) Advanced Analogic Technologies – Backlight/Flash LED Driver and Multiple LDO Lighting Management Unit

PRODUCT DATASHEET
AAT2860
ChargePump^TM Backlight/Flash LED Driver and Multiple LDO Lighting Management Unit
Pin Descriptions
Pin #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
EP
Symbol
OUT
C2+
SDA
SCL
LED_SEL
FL_LVL
(AGND)
LDO_SEL
AGND
LDOC
LDOB
IN
LDOA
BL1
BL2
BL3
BL4
BL5
BL6
(FL1)
BL7
(FL2)
PGND
C2-
C1-
IN
C1+
Description
Charge pump output. OUT is the output of the charge pump and supplies current to the backlight and flash
LEDs. Connect the backlight and flash LED anodes to OUT. Bypass OUT to PGND with a 2.2μF or larger ceramic
capacitor as close to the AAT2860-x as possible.
Positive terminal of charge pump capacitor 2. Connect the 1μF charge pump capacitor 2 from C2+ to C2-.
I²C compatible serial data input. SDA is the data input of the I²C serial interface. Drive SDA with the I²C data.
I²C compatible serial clock input. SCL is the clock input of the I²C serial interface. Drive SCL with the I²C clock.
LED Programming Enable Input. When LED_SEL is strobed low-to-high, the backlight and flash LED registers
can be programmed via the I²C compatible serial interface. When LED_SEL is strobed high-to-low, all backlight
and flash LED outputs are turned off and the backlight and flash LED registers are reset to their default (power-
on-reset or POR) values.
AAT2860-2/3/4: Flash/Torch enable input. When LED_SEL is strobed high and FL_LVL is strobed high, the flash
LED current outputs are enabled and set according to the contents of the flash LED current register. When
FL_LVL is strobed high-to-low, the flash LED outputs return to their low-level programmed values.
AAT2860-1/5: Connect to AGND.
Programming enable input for LDO[A, B, C]. When LDO_SEL is strobed low-to-high, the LDO output voltages can
be programmed via the I²C compatible serial interface. Strobing LDO_SEL high-to-low resets the contents of the
LDO output voltage registers to their default (POR) values and forces all outputs to 0 (zero) volt.
Analog ground. Connect AGND to PGND at a single point as close to the AAT2860-x as possible.
LDOC regulated voltage output. LDOC is the voltage output of LDOC. Bypass LDOC to AGND with a 2.2μF or
larger ceramic capacitor as close to the AAT2860-x as possible.
LDOB regulated voltage output. LDOB is the voltage output of LDOB. Bypass LDOB to AGND with a 2.2μF or
larger ceramic capacitor as close to the AAT2860-x as possible.
Input power pin for all three LDOs. Connect Pin 11 to Pin 23 with as short a PCB trace as practical. Bypassing
this pin with a separate 4.7µF or larger ceramic capacitor will improve performance.
LDOA regulated voltage output. LDOA is the voltage output of LDOA. Bypass LDOA to AGND with a 2.2μF or
larger ceramic capacitor as close to the AAT2860-x as possible.
Backlight LED 1 current sink/channel. BL1 controls the current through backlight LED 1. Connect the cathode of
backlight LED 1 to BL1. If not used, connect BL1 to OUT.
Backlight LED 2 current sink/channel. BL2 controls the current through backlight LED 2. Connect the cathode of
backlight LED 2 to BL2. If not used, connect BL2 to OUT.
Backlight LED 3 current sink/channel. BL3 controls the current through backlight LED 3. Connect the cathode of
backlight LED 3 to BL3. If not used, connect BL3 to OUT.
Backlight LED 4 current sink/channel. BL4 controls the current through backlight LED 4. Connect the cathode of
backlight LED 4 to BL4. If not used, connect BL4 to OUT.
Backlight LED 5 current sink/channel. BL5 controls the current through backlight LED 5. Connect the cathode of
backlight LED 5 to BL5. If not used, connect BL5 to OUT.
AAT2860-1/2/3/5/6: Backlight LED 6 current sink/channel. BL6 controls the current through backlight LED 6.
Connect the cathode of backlight LED 6 to BL6. If not used, connect BL6 to OUT.
AAT2860-4: Flash LED 1 current sink. FL1 controls the current through Flash LED 1. Connect the cathode of
Flash LED 1 to FL1. If not used, connect FL1 to OUT.
AAT2860-1/5/6: Backlight LED 7 current sink/channel. BL7 controls the current through backlight LED 7. Con-
nect the cathode of backlight LED 7 to BL7. If not used, connect BL7 to OUT.
AAT2860-2/3/4: Flash LED or Flash LED 2 current sink. FL2 controls the current through Flash LED 2. Connect
the cathode of Flash LED 2 to FL2. If not used, connect FL2 to OUT.
Power ground. Connect PGND to AGND at a single point as close to the AAT2860-x as possible.
Negative terminal of charge pump capacitor 2.
Negative terminal of charge pump capacitor 1.
Power input. Connect IN to the input source voltage. Bypass IN to PGND with a 4.7μF or larger ceramic capacitor
as close to the AAT2860-x as possible.
Positive terminal of charge pump capacitor 1. Connect the 1μF charge pump capacitor 1 from C1+ to C1-.
Exposed paddle (bottom) Connect to PGND/AGND as close to the AAT2860-x as possible.
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2860.2008.05.1.0