CURRENT MODE PWM CONTROLLER

AP384XC

Data Sheet

1

Jul. 2013 Rev. 2. 0

BCD Semiconductor Manufacturing Limited

General Description

The AP3842C/3C/4C/5C are high performance fixed

frequency current-mode PWM controller series.

These integrated circuits are optimized for off-line and

DC-DC converter applications with minimum external

components. They feature under-voltage lockout

(UVLO) circuit with low start-up current, trimmed

oscillator for precise duty cycle control, current sense

comparator providing maximum current limiting and a

totem pole output stage for increasing output current.

In addition, these ICs also feature accurate protection

against over-temperature, over-current and maximal

output power.

The AP3842C and AP3844C have UVLO thresholds

of 16V(on) and 10V(off); The corresponding thresh-

olds for AP3843C and AP3845C are 8.4 V(on) and

7.6V(off).

The AP3842C and AP3843C can operate approaching

100% duty cycle; AP3844C and AP3845C can operate

from zero to 50% duty cycle.

These ICs are available in SOIC-8 and DIP-8 pack-

ages.

Features

·

Low Start-up Current: 50

·

Low Line Regulation : 4mV

Low Load Regulation : 4mV

·

High Stability of Reference Voltage over a Full

Temperature Range: 0.2mV/

·

Operating Frequency up to 500kHz

·

High PWM Frequency Stability over a Full Tem-

perature Range: 2.5%

·

High PWM Frequency Stability under a Full Sup-

ply Voltage Range: 0.2%

·

Accurate Over-temperature Protection with Hys-

teresis

·

UVLO with Hysteresis

Applications

·

Off-line Converter

·

DC-DC Converter

·

Voltage Adapter

·

CRT Monitor Power Supply

·

Desktop Power Supply

·

DVD/STB Power Supply

SOIC-8

DIP-8

Figure 1. Package Types of AP3842C/3C/4C/5C

Option 1

Option 2