AL8807B Datasheet, PDF (1/18 Pages) Diodes Incorporated – HIGH EFFICIENCY 36V 1.3A PWM DIMMABLE BUCK LED DRIVER

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.
Pin Assignments
SET
GND
GND
CTRL
(Top View)
MSOP-8EP
V_IN
N/C
SW
SW
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)
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. See http://www.diodes.com/quality/lead_free.html for 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
D1 ^R1
V_IN:
6 ~ 36V
C1 ^AL8807B
PWM Dimming
Input:
C2
L1
AL88070B
Document number: DS36191 Rev. 1 - 2
1 of 18
www.diodes.com
March 2014
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