AAT3194 Datasheet, PDF (12/14 Pages) Advanced Analogic Technologies – High Efficiency 1.5X Fractional Charge Pump For White LED Applications

AAT3194
High Efficiency 1.5X Fractional Charge
Pump For White LED Applications
Test Current/Channel Disable
Each channel of the output is equipped with a test
current function. The AAT3194 uses a small (~2µA)
current source injected into each output pin to
detect the presence of an LED. Unused channels
that are tied to ground or LED load fail short will be
automatically diasbled instead of wasting the pro-
grammed output current.
Thermal Protection
The AAT3194 has a thermal protection circuit that
will shut down the charge pump and current out-
puts if the die temperature rises above the thermal
limit.
Application Circuits
Typical AAT3194 Application Circuit:
V_BATTERY
C_IN
C_OUT
1μF
1μF
EN/SET
IN
C1+
OUT
C1-
C2+
AAT3194
C2-
D1
D2
D3
D4
EN/SET
GND
C1
1μF
C2
1μF
D4
D3
D2
D1
T_HI > 50ns
300ns < T_LO < 75μs
50ns minimum to enable
ON/1
2
3
4
5
6
n
(n < =32)
OFF
Enable / Disable / LED Brightness Level Set Data Input
12
3194.2006.09.1.0