PRODUCT DATASHEET
AAT2861
TM
ChargePump
Backlight/Flash LED Driver and Multiple LDO Lighting Management Unit
Flash Driver Control (Address 10 and 11)
Data
LDO C
LDO B
LDO A
The AAT2861-1 and AAT2861-3 are both configured with
a single 600mA LED Flash channel, while the AAT2861-2
is configured with two LED Flash channels each capable
of driving 300mA per channel. Address 10 programs the
flash current level. Table 9 lists the data codes for the
programming Address 10. Upon startup, the power-on-
reset value in Address 10 is set to data code 13.
Controlled by Controlled by Controlled by
1*
2
EN_LDOB/C* EN_LDOB/C*
EN_LDOA*
Controlled by Controlled by
OFF
EN_LDOB/C
EN_LDOB/C
OFF
Controlled by
EN_LDOB/C
Controlled by
EN_LDOA
3
Controlled by
EN_LDOB/C
4
OFF
OFF
Controlled by Controlled by
5
OFF
OFF
EN_LDOB/C
EN_LDOA
Flash Current (mA) per Output
Controlled by
EN_LDOB/C
6
OFF
Data
AAT2861-1 or -3
AAT2861-2
1
2
3
4
5
6
7
8
9
10
11
12
13*
14
15
16
600
560
520
480
440
400
360
320
280
240
200
160
120*
80
300
280
260
240
220
200
180
160
140
120
100
80
Controlled by
EN_LDOA
7
8
OFF
OFF
OFF
OFF
OFF
Table 7: LDO Disable Control (Address 6).
Data
VLDOA (V)
VLDOB (V)
VLDOC (V)
1
2
3
4
5*
6
7
8
9
10
11
12
13
14
15
16
1.2
1.3
1.5
1.6
1.8*
2
2.2
2.5
2.6
2.7
2.8
2.9
3
1.2
1.3
1.5
1.6
1.8*
2
2.2
2.5
2.6
2.7
2.8
2.9
3
1.2
1.3
1.5
1.6
1.8*
2
2.2
2.5
2.6
2.7
2.8
2.9
3
60*
40
20
40
OFF
OFF
Table 9: Flash Current Level (Address 10).
Once the EN/SET pin is pulled high and the AAT2861 has
turned on, the LED Flash channels can be enabled by
pulling the FL_EN to IN. The current setting of the LED
Flash channels can be changed prior to enabling the
flash current, or while the flash current is on.
3.1
3.2
3.3
3.1
3.2
3.3
3.1
3.2
3.3
Table 8: LDO X Output Voltage
(Addresses 7, 8, and 9).
The LED Flash controller also comes with a safety timer
to prevent excessive heat generation and power loss
from extended high current power dissipation. The LED
flash safety timer duration can be set to four values by
writing to Address 11. The default value at startup is 2
seconds. Table 10 shows the Data Codes for the flash
safety timer.
Fast turn-off response time is achieved by an active out-
put pull-down circuit, which is enabled when the LDO
regulator is disabled.
*Denotes default (power-on-reset) value.
w w w . a n a l o g i c t e c h . c o m
18
2861.2009.02.1.2
AAT [ ADVANCED ANALOG TECHNOLOGY, INC. ]
