AAT3113, AAT3114/14A
High Efficiency 1.5X Fractional Charge
Pumps For White LED Applications
Driving white LED display module backlights
and individual white LEDs connected in parallel:
current sources. This feature is particularly useful
to power pre-manufactured display modules that are
pre-wired with white LED backlights connected in a
parallel circuit configuration. All outputs can be con-
nected in parallel to drive groups of LEDs as well.
The internal current source reference circuit bases
feedback from current sensed on the D1 output. For
best operation, the only requirement for this applica-
tion is that the output D1 should always be connect-
ed to the load circuit.
The AAT3114/14A D1 to D6 outputs are true con-
stant current sources capable of driving up to 20mA
each over the operation input voltage range. Since
these outputs are true constant current sources,
they may be connected in parallel to drive a single
power output. Any combination of outputs (D1 to
D6) may be connected in parallel. The maximum
total output current is a sum of parallel-connected
AAT3114/14A Application Driving a Display Module With Six Parallel-Connected White LEDs:
VIN
C1+
C1
1μF
C1-
C2+
OUT
CIN
COUT
C2
1μF
VBATTERY
AAT3114/14A
C2-
1μF
1μF
D1
D2
D3
D4
D5
D6
Display Module
D5 D6
EN/SET
EN/SET
GND
D1
R1
D2
R2
D3
D4
R3
R4
R5
R6
Resistor R is optional
AAT3114/14A Dual Backlight Control Circuit:
VIN
C1+
C1
1μF
C1-
C2+
OUT
C
C
OUT
IN
C2
1μF
V
AAT3114/14A
C2-
BATTERY
1μF
1μF
Keyboard Backlight
D1
D2
D3
D4
D5
D6
Display Backlight
D4
D5
D6
EN/SET
EN/SET
GND
D1
D2
D3
Enable Keyboard Backlight
Enable Display Backlight
3113.2006.07.1.9
13
AAT [ ADVANCED ANALOG TECHNOLOGY, INC. ]
