PRODUCT DATASHEET
AAT2861
TM
ChargePump
Backlight/Flash LED Driver and Multiple LDO Lighting Management Unit
The evaluation board is made flexible so that the user
Evaluation Board User Interface
can disconnect the enable line from the microcontroller
and apply external enable signal. External enable signal
must be applied to the EN/SET pin.
The user interface for the AAT2861 evaluation board is
provided by four buttons and a number of connection
terminals. The board is operated by supplying external
power and pressing individual buttons or button combi-
nations. Table 14 indicates the function of each button or
button combination.
When applying external enable signal, consideration
must be given to the voltage levels. The externally
applied voltage should not exceed the supply voltage
that is applied to the IN pins of the device (DC+).
To power-on the evaluation board, connect a power sup-
ply or battery to the DC- and DC+ terminals. A red LED
indicates that power is applied.
The LDO loads can be connected directly to the evalua-
tion board. For adequate performance, be sure to con-
nect the load between LDOA/LDOB/LDOC and DC- as
opposed to some other GND in the system.
Button(s) Pushed Description
[Push/Release once] LDOA, LDOB and LDOC outputs are programmed to 1.2V. With every subsequent
push/release LDOA, LDOB and LDOC output voltages are incremented according to Table 8.
[Push/hold more than 2 sec] LDOA, LDOB and LDOC outputs will start to cycle through all programmable
voltage settings according to Table 8.
SW1
[Push/Release once] All channels are turned on as Main backlight with 31mA per channel. With every
subsequent push/release the backlight current is decreased according to Table 4.
[Push/hold more than 2 sec] All channels Main and Sub are turned on with 31mA per channel and fade
out sequence is initiated. The cycle proceeds with fade in for Main channels only, followed by fade in se-
quence for Sub channels. When these sequences are finished the program will restart fade out sequence
for all Main and Sub channels.
SW2
[Push/Release once] Flash channels are programmed with maximum current and timer. With every sub-
sequent push/release the flash current is decreased according to Table 9. The FLASH button needs to be
pressed down simultaneously.
SW3
FLASH
This button is connected directly to FL_EN pin. Press and hold for the flash to be enabled.
Table 14: AAT2861 Evaluation Board User Interface.
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AAT [ ADVANCED ANALOG TECHNOLOGY, INC. ]
