AAT2830/31
800mA Total Display Solution
for Portable Devices
Address
THI
Data
TLO
TLAT
EN/SET
1
2
17
18
1
2 . . .
n ≤ 16
0
1
Address
DATA1
DATA0
n
1
1
2
Figure 2: AS Cwire Serial Interface Timing Details.
160
140
120
100
80
A timer function that enables the flash current sinks
for a programmed amount of time is incorporated in
the AAT2830/31. The on-time is programmed by
loading the timing register at Address 6 with a value
from 1 to 16 and by choosing a value for the external
timing capacitor, CT (see Table 9). When data is
latched into the Flash Timing Register, the flash cur-
rent sinks are automatically enabled for the duration
of the programmed time and then disabled. The tim-
ing feature eliminates the need for an external con-
troller to keep track of flash duration. This function
also serves as a protection feature to avoid thermal
damage to the flash LEDs because of software-relat-
ed errors in or disconnection from an external proces-
sor. The flash section's safety timer will only be initi-
ated if writing data to Address 6.
60
40
20
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
Data Code
Figure 3: Address 4, FL1-FL4 Flash
Current Level.
Data
FL1
FL2-FL4
The flash time base T can be calculated by the fol-
lowing equation:
1
2
3
4
Off
Off
On
On
Off
On
Off
On
T = 10 · CT
Where, T is in seconds and CT is in µF.
For example, for a 0.1µF capacitor:
Table 8: Address 5, Torch/Flashlight/Movie Mode
Control; All Channels ON when CT Enabled.
T = 10 · 0.1
= 1s
2830.2007.09.1.0
13
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