AAT2830/31
800mA Total Display Solution
for Portable Devices
For example, to toggle between 1.7% and 25% of the
maximum backlight current on all LEDs, write Data =
14 to Address 3 and Data 4 to Address 0. To set BL1-
BL4 to 25% and BL5-BL6 to 0.2%, write Data = 5 to
Address 3, and Data = 4 to Address 2.
Data BL % of BSET Data BL % of BSET
1
2
3
4
5
6
7
8
0
9
44
51
56
63
71
79
89
100
21
22
25
29
32
35
40
10
11
12
13
14
15
16
BL1-BL4
BL5-BL6
BL %
Data
Current On Current On of BSET
1
2
No
No
No
No
0
0
3
4
5
6
7
8
9
10
11
12
13
14
15
16
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
0
0
Table 2a: Addresses 0-2 with Independent
Channel Control Disabled, Backlight Current
Level.
Yes
Yes
Yes
Yes
No
No
No
No
Yes
Yes
Yes
Yes
0.2
1.7
3.5
7.0
0.2
1.7
3.5
7.0
0.2
1.7
3.5
7.0
Data BL % of BSET Data BL % of BSET
1
2
3
4
5
6
7
8
0
9
44
51
56
63
71
79
89
100
21
22
25
29
32
35
40
10
11
12
13
14
15
16
Table 3: Address 3 with Independent Channel
Control Disabled, Low-Backlight Current
Levels (RBSET = 280kΩ).
Table 2b: Address 1 with Independent
Channel Control Enabled, Backlight
Current Level.
120
100
80
60
40
20
0
Backlight Independent Channel Control
(Address 15)
The AAT2830/31 can also individually control each
backlight channel. This mode allows the user to turn
on some or all of the channels in any desired com-
bination. This control is achieved by changing the
2
functionality of the AS Cwire registers. To enable
individual LED control mode, a user would write
Data 8 to Address 15. All channels that are enabled
must carry the same current, which is set using the
new functionality of Address 1 (see Table 2b).
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
Data Code
Figure 1: Addresses 0-2 Backlight Current Level.
Data
8
Individual BL Control
Low Backlight Current (Address 3)
On
In addition to the current levels set by Addresses 0,
1, and 2 (shown in Table 2a and Figure 1), there is
also a low backlight current level that can be set. To
set the low backlight current level, the user would
write data to Address 3, as shown in Table 3.
Table 4: Address 15, Backlight Independent
Channel Control
2830.2007.09.1.0
11
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