H3842 参数 Datasheet PDF下载

HI-SINCERITY

MICROELECTRONICS CORP.

Spec. No. : HP200202

Issued Date : 1998.08.01

Revised Date : 2002.12.03

Page No. : 1/10

H3842P / HSMC3842

HIGH PERFORMANCE CURRENT MODE CONTROLERS

Description

The H3842P/HSMC3842 are high performance fixed frequency current mode

controllers. They are specifically designed for Off-Line and DC To DC converter

applications offering the designer a cost-effective solution with minimal external

components. These integrated circuits feature a trimmed oscillator for precise duty

DIP-8Pin

cycle control. A temperature compensa-ted reference, high gain error amplifier,

current sensing comparator, and a high current totem pole output ideally suited for

driving a power MOSFET. Also included are protective features consisting of input and reference undervoltage

lockouts each with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single

pulse metering.

Features

•

Trimmed Oscillator for Precise Frequency Control

•

Oscillator Frequency Guaranteed at 250 kHz

•

Current Mode Operation to 500 kHz

•

Automatic Feed Forward Compensation

•

Latching PWM for Cycle-By-Cycle Current Limiting

•

Internally Trimmed Reference with Undervoltage Lockout

•

High Current Totem Pole Output

•

Undervoltage Lockout with Hysteresis

•

Low Startup and Operating Current

Absolute Maximum Ratings

Symbol

Vi

Vi

Io

Eo

Parameter

Supply Voltage (low impedance source)

Supply Voltage (Ii<30mA)

Output Current

Output Energy (capacitive load)

Analog Inputs (pin 2, 3)

Error Amplifier Output Sink Current

Power Dissipation at Tamb≤25

o

C

Storage Temperature Range

Junction Operating Temperature

Lead Temperature (soldering 10s)

Value

30

Self Limiting

±1

5

-0.3 to 5.5

10

1.25

-65 to 150

-40 to 150

300

Unit

V

A

uJ

V

mA

W

o

C

o

C

o

C

Ptot

Tstg

TJ

TL

Block Diagram

Vcc

7

34V

Ground

5

2.50V

VREF Good

Logic

T

2R

R

S

R

1V

Current

Sense

Comparator

UVLO

S/R

5V

REF

Internal

Bias

6

8

VREF

5V 50mA

RT/CT

4

Error AMP.

+

-

OSC

Output

VFB

COMP

Current

Sense

2

1

3

PWM Latch

H3842P

HSMC Product Specification