AP1509

Document number: DS31016 Rev. 6 - 2

1 of 12

www.diodes.com

February 2020

© Diodes Incorporated

AP1509

150kHz, 2A PWM BUCK DC-DC CONVERTER

Description

The AP1509 series are monolithic ICs designed for a step-down

DC-DC converter and have the ability of driving a 2A load without an

additional transistor, which saves board space.

The external shutdown function can be controlled by logic level and

then go into standby mode. The internal compensation makes

feedback control have good line and load regulation without external

design. Regarding protected function, thermal shutdown prevents

overtemperature operating from damage, and current limit works

against overcurrent operating of the output switch. If current limit

function occurs, and VFB is below 0.5V, the switching frequency is

reduced. The AP1509 series operates at a switching frequency of

150kHz thus allowing smaller-sized filter components than what is

required 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 SO-8 package.

Pin Assignments

(Top View)

1

2

3

4

8

7

6

5

VIN

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 of 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 up to 22V

•

Output Load Current: 2A

•

Low Power Standby Mode

•

Built-in Switching Transistor On Chip

•

Totally Lead-Free & Fully RoHS Compliant (Note 1 & 2)

•

Halogen and Antimony Free.

“Green” Device (Note 3)

•

For automotive applications requiring specific change

control (i.e. parts qualified to AEC-Q100/101/200, PPAP

capable, and manufactured in IATF 16949 certified facilities),

please contact us or your local Diodes representative.

https://www.diodes.com/quality/product-definitions/

Applications

•

Simple High-Efficiency Step-Down Regulator

•

On-Card Switching Regulators

•

Positive to Negative Converter

Notes:

1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant.

2. See https://www.diodes.com/quality/lead-

free/ 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.