AL9902

Document number: DS37878 Rev. 1 - 2

1 of 18

www.diodes.com

July 2015

© Diodes Incorporated

AL9902

LINEAR AND PWM DIMMING HIGH VOLTAGE LED DRIVER

Description

The AL9902 high-voltage PWM LED driver provides an efficient

solution for offline high-brightness LED lamps from rectified line

internal MOSFET that allows switching frequencies up to 300kHz,

with the switching frequency determined by an external single

resistor. The AL9902 topology creates a constant current through the

LEDs

providing constant

light output.

The output

current

is

programmed by one external resistor.

The LED brightness can be varied by both linear and PWM dimming

using the AL9902

’s LD and PWM pins respectively. The PWM input

operates with duty ratio of 0-100% and frequency of up to several

kHz.

The AL9902 is available in the thermally enhanced U-DFN6040-12

and SO-16 packages.

Features



>90% Efficiency





Internal MOSFET Up to 650V, 2A



High Switching Frequency Up to 300kHz



Internal Voltage Regulator Removes Start-Up Resistor



7.5V Regulated Output



Tighter Current Sense Tolerance Better Than ±5%



LED Brightness Control with Linear and PWM Dimming



Internal Over-Temperature Protection (OTP)



U-DFN6040-12 and SO-16 Packages



Totally Lead-Free & Fully RoHS compliant (Notes 1 & 2)



Halogen and Antimony Free. “Green” Device (Note 3)

Pin Assignments

7

12

6

6

11

6

2

3

4

5

6

1

8

9

10

11

7

12

NC

NC

PWM VDD

LD

Rosc

SW

NC

SO

GND

CS

VIN

EP1

EP2

U-DFN6040-12

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

NC

NC

SW

NC

PWM VDD

LD

Rosc

NC

VIN

CS

GND

NC

NC

SO

NC

SO-16

Applications



LED Offline Lamps



High Voltage DC-DC LED Driver



Signage and Decorative LED Lighting



Back Lighting of Flat Panel Displays



General Purpose Constant Current Source

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 Applications Circuit

AC+

AC-

C1

C2

C3

Rsense

Rosc

D1

GND

AL9902

PWM

LD

VDD

CS

Rosc

SO

SW

VIN

L1

3

HD06

1

2

4

Z1

602V