HT3402S

1/11

40V/2A Constant Voltage & Constant Current Buck Converter IC

www.hotchip.com.cn

Ver1.1

General Description

The HT3402S is a constant current, constant

voltage power supply converter, which utilizes

a voltage

mode,

a current mode circuit, and

pulse

width

modulation

(PWM)

switching

regulator control circuit

An external sense resistor will set the charge

current.

An

internal

resistor

divider

and

precision reference

set

the

final

float

voltage

to 5.1V

with ± 3% accuracy. With

a 150 KHz switching frequency, HT3402S can

provide

a

simple

solution

against

EMI.

High efficiency up to 90% can also diminish

heat significantly on all related components.

The HT3402S also possesses over-voltage

protect, over-thermal protect, and short- circuit

protect function. At the beginning of the

charge, the over- current circuit will limit the

charge current not too high.

The HT3402S is available in a 8- pin SOP8

package

Features



Wide Input Supply Range: 10V to 40V



±3% Charge Voltage Accuracy；



High Efficiency Current Mode PWM

Control with 150KHz Switching Frequency



Constant Switching Frequency for

Minimum Noise



Cable compensation function



Automatic Battery Recharge



Automatic Shutdown When Input Supply

Removed



Available in a 8-pin SOP8 package

Applications



SMPS



Charger



Portable Computers



Handheld Instruments

5.1V Output

INput

C1

47uF/50V

C2

470uF/10V

C3

0.1uF/50V

Rvc

Rsen

Rsen=0.03/Iout

L1

47uH

D1

SS34

VIN

VC

VSEN

VOUT

GND

GND

SW

SW

U1

HT3402

1

2

3

4

8

7

6

5

Typical Application Circuitry