AP3790

Document number: DS37221 Rev. 3 - 2

1 of 17

www.diodes.com

October 2014

© Diodes Incorporated

AP3790

A Product Line of

Diodes Incorporated

PUMP EXPRESS

Description

The AP3790 is a high accuracy and low cost switching mode power

supply controller to drive power bipolar transistor for battery

charger/adapter applications. The controller regulates the output

voltage and current in the primary side by piece-wise Pulse

Frequency Modulation (p-PFM) in discontinuous conduction mode

(DCM). The controller uses adaptive source current to optimize

driving current to reduce driving loss. The system operating frequency

reduces linearly from heavy load to light load in each interval of the p-

PFM, and enters constant current mode when the load current is

equal to the maximum system output current.

The output voltage of AP3790 can be adjusted based on the patterns

of load current aligned to MTK Pump Express protocol.

The AP3790 provides operating frequency Jitter function from light to

full load range to improve the power supply EMI performance. The

AP3790 also has built-in fixed cable voltage drop compensation (6%

of nominal system output voltage) and adjustable line voltage

compensation.

The AP3790 can work individually to achieve Ultra-Low standby

power under 5V output.

The AP3790 is packaged in SO-8.

Applications



Adapters/Chargers

Pin Assignments

(Top View)

1

2

3

4

8

7

6

5

GND

FB

NC

OUT

NC

CS

VCC

CPC

SO-8

Features



Compatible to MediaTek Pump Express



Ultra-Low Standby Power Consumption



Valley-turn On to Reduce Switching Loss and Benefit for EMI



Piece-wise

Frequency

Reduction

to

Enhance

Conversion

Efficiency and Suppress Audio Noise



±5% Constant Voltage Accuracy for 5V Output



Audio Noise Suppression



Open Circuit Protection (OCkP)



Current Sense Resistor Short Protection



Over Voltage Protection (OVP)



Over Temperature Protection (OTP)



Short Circuit Protection (SCP) with Hiccup



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



Halogen and Antimony Free.

“Green” Device (Note 3)

Notes:

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

2. See http://www.diodes.com/quality/lead_free.html

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.