Diodes AL8807B User Manual
Al8807b, 6 ~ 36v, New prod uc t al8807b
AL88070B
Document number: DS36191 Rev. 1 - 2
1 of 18
March 2014
© Diodes Incorporated
NEW PROD
UC
T
AL8807B
HIGH EFFICIENCY 36V 1.3A PWM DIMMABLE BUCK LED DRIVER
Description
The AL8807B is a step-down DC/DC converter designed to drive
LEDs with a constant current. The device can drive up to 9 LEDs,
depending on the forward voltage of the LEDs, in series from a
voltage source of 6V to 36V. Series connection of the LEDs provides
identical LED currents resulting in uniform brightness and eliminating
the need for ballast resistors. The AL8807B switches at frequency up
to 1MHz with controlled rise and fall times to reduce EMI. This
allows the use of small size external components, hence minimizing
the PCB area needed.
Maximum output current of AL8807B is set via an external resistor
connected between the V
IN
and SET input pins. Dimming is
achieved by applying a PWM signal at the CTRL input pin. An input
voltage of 0.4V or lower at CTRL switches off the output MOSFET
simplifying PWM dimming.
Features
LED driving current up to 1.3A
Better than 5% accuracy
High efficiency up to 96%
Optimally controlled switching speeds
Operating input voltage from 6V to 36V
PWM input for dimming control
Open-Circuit LED protection
LED Chain Short Circuited
Over-Temperature
Protection
MSOP-8EP Available in “Green” Molding Compound (No Br,
Sb) with lead Free Finish/ RoHS Compliant
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Pin Assignments
Applications
MR16
lamps
General illumination lamps
12V powered LED Lamps
24V powered LED Lamps
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. S more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free,
"Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl)
and <1000ppm antimony compounds.
Typical Application Circuit
(Top View)
MSOP-8EP
SET
GND
GND
CTRL
V
IN
N/C
SW
SW
AL8807B
V
IN
SET
SW
CT
R
L
GN
D
C2
R1
C1
D1
L1
PWM Dimming
Input:
V
IN
:
6 ~ 36V