AAT2860 Datasheet, PDF (16/23 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
REG2
REG3
REG5
D7
X³
FLOOR[1]
X³
D6
MEQS²
FLOOR[0]
X³
D5
MAIN_ON
SUB_ON
X³
D4
WM[4]
WS[4]
X³
D3
WM[3]
WS[3]
X³
D2
WM[2]
WS[2]
X³
D1
WM[1]
WS[1]
NOFADE_M²
D0
WM[0]
WS[0]
NOFADE_S²
Table 3: AAT2860 BL1-BLX Backlight Control Register Allocation.
WM[4:0], WS[4:0]
00000¹
00001
00010
00011
00100
00101
00110
00111
01000
01001
01010
01011
01100
01101
01110
01111
LED Current (mA)
31¹
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
WM[4:0], WS[4:0]
10000
10001
10010
10011
10100
10101
10110
10111
11000
11001
11010
11011
11100
11101
11110
11111
Table 4: MAIN/SUB LED Current - WM/WS[4:0].
LED Current (mA)
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0.5
FLOOR[1:0]
00¹
01
10
11
Fade In/Out Current Level (mA)
0.48
0.97
1.94
2.90
Table 5: Main/Sub LED Current
Fade In/Out Level Control.
Part
Number
AAT2860-2
AAT2860-3
AAT2860-4
MEQS Bit (REG2 Data Bit[6])
“1” (Default)
6M+0S+1FL
6M+0S+1FL
5M+0S+2FL
“0”
4M+2S+1FL
5M+1S+1FL
4M+1S+2FL
Table 6: AAT2860-2/3/4 Flash Driver
Control Register Allocation.
For each one of the three options in Table 6, setting/pro-
gramming the bits in REG4 (see Table 7) sets the full-
scale flash current, the torch current levels, and flash
safety time duration. The most-significant 4-bit nibble
(REG1[D7:D4], or F_HI[3:0]) of the 8-bit data word sets
the full-scale flash LED current, the middle two bits
(REG4[D3:D2], or F_TIME[1:0]) set the flash safety dura-
tion, and the last two bits (REG4[D1:D0], or F_LO[1:0])
are used to set the torch current level.
1. Denotes default (power-on-reset) value.
2. Denotes default value is "1" or ON.
3. Don't Care or Reserved.
16
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2860.2008.05.1.0