AS1101_1 Datasheet, PDF (1/13 Pages) ams AG – Low-Dropout LED Drivers

AS1101, AS1102, AS1103, AS1104
Low-Dropout LED Drivers
Data Sheet
1 General Description
The AS1101/AS1102/AS1103/AS1104 are LED drivers
designed to match current source bias for any color
LED, including white and blue. The devices can drive up
to 4 high-current LEDs, and the LED current is program-
mable using an external resistor (RSET).
The AS1101 LED currents are 460 x ISET (per LED, typ)
at an LED cathode voltage (VSAT) of 150mV and 650 x
ISET (typ) at a VSAT of 1V, where ISET is the current
through RSET connected to pin CTRL.
The AS1102, AS1103, and AS1104 LED currents are
230 x ISET (per LED, typ) at a VSAT of 150mV and 325 x
ISET (typ) at a VSAT of 1V.
The AS1101, AS1102, and AS1104 incorporate a chip-
enable feature via pin ON. When the devices are dis-
abled, the supply current drops to less than 1µA.
The AS1101, AS1102, and AS1103 are available in a
6-pin SC70 package; the AS1104 is available in a 8-pin
MSOP package.
2 Key Features
! LED Drivers for Parallel-Connected LEDs
! Ultra-Low Voltage Drop: Less Than 150mV (for Li-
ion Battery Support)
! Analog and PWM Brightness Control
! Up to 80mA per LED (AS1101)
! Up to 40mA per LED (AS1102, AS1103, AS1104)
! No Electromagnetic Interference, No Switching-
Noise
! Current-Matching Requires No External Compo-
nents
! Active-Low Shutdown Mode (AS1101, AS1102,
and AS1103)
! Low Shutdown-Current: Less Than 1µA
! SC70-6 Package (AS1101, AS1102, and AS1103)
! MSOP-8 Package (AS1104)
Figure 1. Typical Application Diagrams
2 Diode Control with Enable
VIN
3 Applications
The AS110x devices are ideal for LED displays and key-
board backlights, as well as lighting management units
for battery powered audio devices such as MP3 and CD
players, mobile and cordless phones, PDAs, portable
DVD players, and consumer electronics.
3 Diode Control with Enable
VIN
VSET
(3V)
ISET
I1/I2 VSAT
I3/I4
RSET CTRL
AS1101
ENABLE
ON
GND
I1 VSAT I2
I3
VSET
(3V)
ISET
RSET CTRL
AS1102
ENABLE
ON
GND
4 Diode Control
VIN
I1 VSAT I2
I3
I4
VSET
(3V)
ISET
RSET CTRL
AS1103
GND
4 Diode Control with Enable
VIN
I1 VSAT I2
I3
I4
VSET
(3V)
ISET
RSET CTRL
AS1104
ENABLE
ON
GND
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