AP3445/L

Document number: DS39755 Rev. 1 - 2

1 of 13

www.diodes.com

March 2018

© Diodes Incorporated

AP3445/L

1MHZ, 2A STEP-DOWN DC-DC BUCK CONVERTER

Description

The AP3445 and AP3445L is a 2A step-down DC-DC converter. At

heavy load, the constant-frequency PWM control performs excellent

stability

and

transient

response.

No

external

compensation

components are required.

The AP3445/L supports a range of input voltages from 2.7V to 5.5V

allowing the use of a single Li+/Li-polymer cell, multiple Alkaline/NiMH

cell, and other standard power sources. The output voltage is

adjustable from 0.6V to the input voltage. The AP3445/L employs

internal power switch and synchronous rectifier to minimize external

part count and realize high efficiency. During shutdown, the input is

disconnected from the output and the shutdown current is less than

1μA. Other key features include over-temperature and short circuit

protection, and under-voltage lockout to prevent deep battery

discharge.

The AP3445/L delivers 2A maximum output current while consuming

only 55

MOSFETs and 100% duty cycle operation make the AP3445/L an

ideal choice for high output voltage, high current applications which

require a low dropout threshold. Pulse skip mode to maintain high

efficiency at light-load conditions.

The AP3445/L is available in SOT26 (SC74R) package.

Features



Input Voltage: 2.7V to 5.5V





0.6V Reference Voltage with ±1.5% Precision



55µA (Typ) No Load Quiescent Current



Shutdown Current: <1µA



100% Duty Cycle Operation



1MHz Switching Frequency



No External Compensation Required



Short Circuit Protection

445L: Latch Off Protection

AP3445: Hiccup Mode Protection



Over Voltage Protection

3445L: Latch Off Protection

445: Non Latch Off Protection



Thermal Shutdown



SOT26 (SC74R) Package



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



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

Pin Assignments

(Top View)

SOT26 (SC74R)

Applications



Post DC-DC Voltage Regulation



Set Top Boxes



Notebook Computer



PAD

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.

EN

LX

VIN

FB

GND

PG

1

2

3

4

5

Pin 1 Mark

6