AAT2846 Datasheet, PDF (21/25 Pages) Advanced Analogic Technologies – High Current Charge Pump with Dual LDO for Backlight and Flash Applications

AAT2846
High Current Charge Pump with Dual LDO
for Backlight and Flash Applications
Button(s) Pushed
DATA
LIGHT
LIGHT+DATA
MOVIE
MOVIE+DATA
FLASH
FLASH+DATA
LIGHT+MOVIE+FLASH
Description
Increment the data setting for the most recently activated mode. With backlight or
movie mode activated, hold down the button to auto-cycle through the brightness levels.
Toggle ON/OFF the backlighting section. Set the brightness level using the DATA button
(defaults to Data 1).
Decrement the brightness setting for backlight mode. Hold down to auto-cycle.
Toggle ON/OFF movie mode illumination. Set the brightness level using the DATA but-
ton (defaults to Data 10).
Decrement the brightness setting for movie mode. Hold down to auto-cycle.
Generate a flash pulse. Pulse duration is the lesser of 2 seconds or the CT value result.
Set the brightness level using the DATA button (defaults to Data 1).
Toggle ON/OFF the LDOs.
Reset. Clear all data and bring all enable lines low.
Table 11: AAT2846 Evaluation Board User Interface.
Evaluation Board Schematics
DC+
J1
123
D1 D2 D3 D4 D5 D6
VIN
C12
100μF
optional 100μF
lab supply bypass
ENLA
D7 D8
VOUT
280K yields
300mA/chnl
max flash
R10
280K
U1
ENFL
CTRL_CT
C9
0.1μF
C8
0.1μF
OUTB
Programmed for 2.8V
output by default
1
D3
2
D2
3
D1
4
AGND
5
CT
6
CREF
7
FBB
21
F2
20
ENS
19
PGND
18
IN
17
C2-
16
C2+
15
ENB
C2
1.0μF
8 9 10 11 12 13 14
R11
160K
R12
120K
C6
2.2μF
C5
2.2μF
C1
1.0μF
R13
60.4K
C7
2.2μF
R14
120K
Programmed for 1.8V
output by default
C4
4.7μF
VOUT
C3
2.2μF
2846.2007.08.1.0
Figure 8: AAT2846 Section Schematic
ENBL
ENLB
OUTA
21