AAT2856 AAT, AAT2856 Datasheet - Page 13

• Manufacturer Part Number: AAT2856
• Description: High Current Charge Pump
• Manufacturer: AAT

Since only one of the scales can be active at any
given time, the 20mA and 30mA scales cannot be
mixed between main and sub. When setting Address
12 to the 30mA scale, only current levels from that
scale can be mixed between main and sub.
Backlight Independent Channel Control
(Address 15)
The AAT2856 has a unique independent channel
control mode whereby individual backlight LED
channels can be enabled and disabled to form a
custom arrangement of active channels.
To enable independent channel control mode, write
Data 8 to Address 15. To exit individual mode con-
trol, the AAT2856 state machine can be reset by
strobing ENS low and holding ENS low longer than
the A
With independent channel control mode enabled,
Addresses 2 and 3 are re-mapped according to
Tables 8 and 9. As indicated by the possible set-
tings listed in the tables, any combination of back-
lighting channels can be enabled and disabled.
2856.2007.06.1.0
Table 6: Address 12 Maximum Current
Data
2
SCwire's t
8
Table 7: Address 15, Independent
Data
1
2
Backlight Control.
OFF
Individual Backlight Control
latch time.
Settings.
Maximum Current
On
20mA
30mA
Dual LDO for BacklightApplications
Because Addresses 2 and 3 are re-mapped when
independent channel control mode is enabled, the
functions originally assigned to Addresses 2 and 3
are no longer available.
High Current Charge Pump with
Data
10
12
13
14
15
16
11
1
2
3
4
5
6
7
8
9
Table 9: Sub-Address 3: BL1 and BL2
Data
10
12
13
14
15
16
Table 8: Sub-Address 2: BL3-BL6
11
1
2
3
4
5
6
7
8
9
BL6
Off
Off
Off
Off
Off
Off
Off
Off
On
On
On
On
On
On
On
On
On/Off Control.
On/Off Control.
BL2
BL5
Off
Off
Off
Off
Off
Off
Off
Off
On
On
On
On
On
On
On
On
Off
Off
Off
Off
On
On
On
On
Off
Off
Off
Off
On
On
On
On
BL4
AAT2856
Off
Off
On
On
Off
Off
On
On
Off
Off
On
On
Off
Off
On
On
BL1
Off
Off
Off
Off
On
On
On
On
Off
Off
Off
Off
On
On
On
On
BL3
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
Off
On
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