AL8807EV3

Issue 1 – December 2011

www.diodes.com

© Diodes Incorporated 2011

2

AL8807EV3 Connection Point Definition

Name

Description

Vin

Positive supply voltage. 6 to 36V

GND

Supply Ground (0V).

CTRL

Internal voltage ref. pin (2.5V). This pin can be used to achieve dimming and for

switching the output current off.

Leave floating for normal operation.

LED A

LED A

connects to the external LED anode

LED K

LED K

connects to the external LED cathode

AL8807 DEVICE DESCRIPTION

The AL8807 is a continuous mode inductive driver in a SOT25 package, for driving one or more

series-connected LEDs efficiently from a voltage source higher than the LED voltage. The device

includes the output switch and a current sense circuit, which requires an external sense resistor to set

the nominal current up to 1A.

AL8807 DEVICE FEATURES

•

Drives one or more series-connected LEDs

•

LEDs up to 1A.

•

Internal 40V switch.

•

Wide input voltage: 6V to 36V.

•

Inherent open circuit LED protection.

•

Brightness control using DC or PWM.

DEVICE APPLICATIONS

•

LED flashlights.

•

High Power LED driving.

•

Low-voltage halogen replacement LEDs.

•

Automotive lighting.

•

Illuminated signs.

AL8807 Device Packages, Pin and Definitions

1

2

3

4

5

6

7

8

GND

CTRL

GND

N.C.

SET

SW

SW

Top View

SOT25 package

MSOP8EP package

AL8807 Device Pin Definition

Name

Pin No

Description

SW

1

Drain of NDMOS switch.

GND

2

Ground (0V).

CTRL

3

Internal voltage ref. pin (2.5V) :

•

Leave floating for normal operation.

•

Connect to GND to turn off output current.

•

Drive with DC voltage (0.4V to 2.5V) or with PWM (up to 5V

logic level) signal to adjust output current

SET

4

Connect a sense resistor, R1, from the SET pin to VIN to sense the

VIN

5

Input voltage: 6V to 36V. Decouple to ground with a 2.2uF or higher

ceramic capacitor.