AP1509

150KHz, 2A PWM BUCK DC/DC CONVERTER

AP1509

Document number: DS31016 Rev. 4 - 2

1 of 13

www.diodes.com

June 2010

© Diodes Incorporated

Description

The AP1509 series are monolithic IC designed for a step-

down DC/DC converter, and own the ability of driving a

2A load without additional transistor. It saves board space.

The external shutdown function can be controlled by logic

level and then come into standby mode. The internal

compensation makes feedback control having good line and

load regulation without external design. Regarding protected

function, thermal shutdown is to prevent over temperature

operating from damage, and current limit is against over

current operating of the output switch. If current limit function

will be reduced. The AP1509 series operates at a switching

frequency

of

150KHz

thus

allow

smaller

sized

filter

components than what would be needed with lower frequency

switching regulators. Other features include a guaranteed

+4% tolerance on output voltage under specified input voltage

and output load conditions, and +15% on the oscillator

frequency. The output version included fixed 3.3V, 5V, 12V,

and an adjustable type. The chips are available in a standard

8-lead SOP-8 package.

Pin Assignments

(Top View)

1

2

3

4

8

7

6

5

GND

FB

AP1509

GND

Output

GND

GND

SD

SOP-8L

Features

•

Output Voltage: 3.3V, 5V, 12V and Adjustable Output

Version

•

Adjustable Version Output Voltage Range, 1.23V to

18V+4%

•

150KHz +15% Fixed Switching Frequency

•

Voltage Mode Non-Synchronous PWM Control

•

Thermal-Shutdown and Current-Limit Protection

•

ON/OFF Shutdown Control Input

•

Operating Voltage can be up to 22V

•

Output Load Current: 2A

•

SOP-8L Packages

•

Low Power Standby Mode

•

Built-in Switching Transistor On Chip

•

SOP-8L: Available in “Green” Molding Compound

(No Br, Sb)

•

Lead Free Finish/ RoHS Compliant (Note 1)

Applications

•

Simple High-Efficiency Step-Down Regulator

•

On-Card Switching Regulators

•

Positive to Negative Converter

Notes:

1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at

http://www.diodes.com/products/lead_free.html.