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Copyright © 2015 Active-Semi, Inc.

ACT4525

40V/3.5A CV/CC Buck Converter with USB Auto –Detect

FEATURES

and BC1.2 Devices

APPLICATIONS

GENERAL DESCRIPTION

ACT4525 is a wide input voltage, high efficiency

step-down DC/DC converter that operates in either

CV (Constant Output Voltage) mode or CC

(Constant Output Current) mode. ACT4525 has

separated output current limits for dual port CLA

applications. With the separated current limits, the

CLA can meet Apple’s MFi standard. ACT4525

provides up to 3.5A output current at 125kHz

switching frequency. ACT4525 builds in USB auto-

detect algorithms to recognize Apple, Samsung,

and BC1.2 devices to ensure maximum charge

current to attached devices. ACT4525 utilize

adaptive drive technique to achieve good EMI

performance while main 90% efficiency at full load

for mini size CLA designs. ACT4525 also built in

output short circuit protection with hiccup mode.

The average output current is reduced to below

6mA when output is shorted to ground. Other

features include output over voltage protection and

thermal shutdown.

The devices are available in a SOP-8EP package

and require very few external devices for operation.

2.4A

2.9A

5.25V

4.95V

5.10V

Vout1

Iout1

3.20V

Typical Application Circuit

ACT4525

HSB

IN

SW

4.5V to 40V

DM

Rcs1

25mΩ

CSP

DP

Vout

GND

D-

D+

GND

CSN1

5.1V/2.4A

C2

10μF

C3

22nF

C5

470μF

C1

47μF

C4

10μF

C6

2.2μF

D1

SK54L

L1

33μH

Vout

GND

D-

D+

5.1V/1A

CSN2

Rcs2

50mΩ

C7

2.2μF

* Patent Pending

V/I Profile

1.1A

1.3A

5.25V

4.95V

5.10V

Vout2

Iout2

3.20V