Diodes AL8843EV1 User Manual

General Description
The AL8843 is a hysteresis mode DC-DC
step-down converter, designed for driving
single or multiple series connected LEDs
efficiently from a voltage source higher
than the LED voltage. The device can
operate from an input supply between 4.5V
and 40V and provide
adjustable output current up to 3A.
Depending upon
external components, this converter can
provide up to 60W of output power.
The AL8843 integrates the power switch
and a high-side output current sensing
circuit, which uses an external resistor to
set the nominal average output current.
Dimming can be realized by applying an
external control signal to the CTRL Pin. The
CTRL Pin will accept either a DC voltage
signal or a PWM signal.
The soft-start time can be adjusted by an
external capacitor from the CTRL Pin to
Ground. Applying a voltage of 0.3V or lower
to the CTRL Pin will shut down the power
switch.
AL8843EV1
Dec 2017
www.diodes.com
an externally
supply voltage and
AL8843EV1 User Guide
Applications
 LED Retrofit for Low Voltage Halogen
 Low Voltage Industrial Lighting
 LED Backlighting
 Illuminated Signs
 External Driver with Multiple Channels
Key Features
 Wide Input Voltage Range: 4.5V to 40V
 Output Current up to 3A
 Internal 40V NDMOS Switch
 Typical 4% Output Current Accuracy
 Single Pin for On/Off and Brightness
Control by DC Voltage or PWM Signal
 Recommended Analog Dimming Range:
10% to 100%
 Soft-Start
 High Efficiency (Up to 97%)
 LED Short Protection
 Inherent Open-Circuit LED Protection
 Over Temperature Protection (OTP)
 Up to 1MHz Switching Frequency
 SO-8EP Packages Available in Green
Molding Compound (No Br, Sb)
AL8843EV1 Specifications
Parameter Value
Input Voltage 5V
LED Current 2A
Number of LEDs 1~10 LEDs
XYZ Dimension 63mm x 40mm x 10mm
to 40V
DC DC
Page 1 of 10