AP3781

Document number: DS42518 Rev. 2 - 2

2 of 15

www.diodes.com

May 2020

© Diodes Incorporated

AP3781

Typical Applications Circuit

C2

FR1

D2

T1

D3

FB

R8

OUT

R10

R9

CS

C4

U1

GND VCC

R1

R2

Q1

12V/2A

C5

R11

C7

DB1

R3

R4

C3

D1

C6

CY1

AP3781

R12

C1

Np

Ns

Na

+

+

+

+

+

L1

R5

NTC

OTP

R6

R7

Pin Descriptions

Pin Number

Pin Name

Function

1

GND

The ground of the controller

2

FB

The CV regulation is realized based on the voltage sampling of this pin

3

VCC

The VCC pin supplies the power for the IC

4

CS

The CS is the current sense pin of the IC. The IC will turn off the power MOSFET

according to the voltage on the CS pin

5

OTP

Adjustable over temperature protection by external NTC resistor

6

NC

No Connection

7

OUT

Output pin to drive external MOSFET

8

NC

No Connection