AP64501

Document number: DS41980 Rev. 4 - 2

1 of 26

www.diodes.com

August 2019

© Diodes Incorporated

AP64501

3.8V TO 40V INPUT, 5A LOW IQ SYNCHRONOUS BUCK WITH PROGRAMMABLE SOFT-START TIME

Description

The AP64501 is a 5A, synchronous buck converter with a wide input

voltage range of 3.8V to 40V. The device fully integrates a 45

mΩ high-

side power MOSFET and a 20

mΩ low-side power MOSFET to provide

high-efficiency step-down DC-DC conversion.

The AP64501 device is easily used by minimizing the external

component count due to its adoption of peak current mode control.

The AP64501 design is optimized for Electromagnetic Interference

(EMI) reduction. The device has a proprietary gate driver scheme to

resist switching node ringing without sacrificing MOSFET turn-on and

turn-off times, which reduces high-frequency radiated EMI noise

caused by MOSFET switching. AP64501 also features Frequency

Spread Spectrum (FSS) with a switching frequency jitter of ±6%,

which reduces EMI by not allowing emitted energy to stay in any one

frequency for a significant period of time.

The device is available in an SO-8EP package.

Features



VIN 3.8V to 40V



5A Continuous Output Current



0.8V ± 1% Reference Voltage



25µA Low Quiescent Current (Pulse Frequency Modulation)



570kHz Switching Frequency



Programmable Soft-Start Time



Up to 85% Efficiency at 5mA Light Load



Proprietary Gate Driver Design for Best EMI Reduction



Frequency Spread Spectrum (FSS) to Reduce EMI



Low-Dropout (LDO) Mode



Precision Enable Threshold to Adjust UVLO



Protection Circuitry

o

Undervoltage Lockout (UVLO)

o

Output Overvoltage Protection (OVP)

o

Cycle-by-Cycle Peak Current Limit

o

Thermal Shutdown



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



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

Pin Assignments

EXPOSED PAD

9

1

2

3

4

5

6

7

8

BST

VIN

EN

SS

FB

COMP

GND

SW

TOP VIEW

SO-8EP

Applications



5V, 12V, and 24V Distributed Power Bus Supplies



Power Tools and Laser Printers



White Goods and Small Home Appliances



Home Audio



Network Systems



Consumer Electronics



General Purpose Point of Load

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.