General Description

The MAX5094A/B/C/D/MAX5095A/B/C BiCMOS, high-

performance, current-mode PWM controllers have all the

features required for wide input-voltage range

isolated/nonisolated power supplies. These controllers

are used for low- and high-power universal input volt-

age and telecom power supplies.

The MAX5094/MAX5095 contain a fast comparator with

only 60ns typical delay from current sense to the output

for overcurrent protection. The MAX5094 has an inte-

grated error amplifier with the output at COMP. Soft-

start is achieved by controlling the COMP voltage rise

using external components.

The oscillator frequency is adjustable from 20kHz to

1MHz with an external resistor and capacitor. The tim-

ing capacitor discharge current is trimmed allowing for

programmable dead time and maximum duty cycle for

a given frequency. The available saw-toothed waveform

needed.

The MAX5095A/MAX5095B include a bidirectional syn-

chronization circuit allowing for multiple controllers to

run at the same frequency to avoid beat frequencies.

Synchronization is accomplished by simply connecting

the SYNC of all devices together. When synchronizing

with other devices, the MAX5095A/MAX5095B with the

highest frequency synchronizes the other devices.

Alternatively, the MAX5095A/MAX5095B can be syn-

chronized to an external clock with an open-drain out-

put stage running at a higher frequency.

The MAX5095C provides a clock output pulse

(ADV_CLK) that leads the driver output (OUT) by

110ns. The advanced clock signal is used to drive the

secondary-side synchronous rectifiers.

The MAX5094A/B/C are available in the 8-pin SO and

MAX5095A/B/C are available in the 8-pin µMAX pack-

age. All devices operate over the automotive tempera-

ture range of -40°C to +125°C.

Applications

Universal Input AC/DC Power Supplies

Isolated Telecom Power Supplies

Isolated Power-Supply Modules

Networking Systems

Computer Systems/Servers

Industrial Power Conversion

Isolated Keep-Alive Circuits

Features

♦ Pin-for-Pin Replacement for UCC28C43

(MAX5094A) and UCC28C45 (MAX5094B)

♦ 2A Drive Source and 1A Sink Capability

♦ Up to 1MHz Switching Frequency Operation

♦ Bidirectional Frequency Synchronization

(MAX5095A/MAX5095B)

♦ Advanced Output Drive for Secondary-Side

Synchronous Rectification (MAX5095C)

♦ Fast 60ns Cycle-by-Cycle Current Limit

♦ Trimmed Oscillator Capacitor Discharge Current

Sets Maximum Duty Cycle Accurately

♦ Accurate ±5% Start Voltage with 0.8V Hysteresis

♦ Low 32µA Startup Current

♦ 5V Regulator Output (REF) with 20mA Capability

♦ Versions with 0.3V Current-Sense Threshold

♦ Overtemperature Shutdown

High-Performance, Single-Ended, Current-Mode

PWM Controllers

________________________________________________________________ Maxim Integrated Products

1

OUT

GND

1

2

8

7

REF

FB

CS

COMP

µMAX/SO

TOP VIEW

3

4

6

5

MAX5094

Pin Configurations

Ordering Information

19-3864; Rev 3; 10/06

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART

TEMP RANGE

PIN-

PACKAGE

PKG

CODE

MAX5094AASA

-40°C to +125°C

8 SO

S8-4

MAX5094AASA+

-40°C to +125°C

8 SO

S8-4

MAX5094AAUA*

-40°C to +125°C

8 µMAX

U8-1

MAX5094AAUA+

-40°C to +125°C

8 µMAX

U8-1

MAX5094BASA*

-40°C to +125°C

8 SO

S8-4

MAX5094BASA+

-40°C to +125°C

8 SO

S8-4

MAX5094BAUA*

-40°C to +125°C

8 µMAX

U8-1

MAX5094BAUA+

-40°C to +125°C

8 µMAX

U8-1

Pin Configurations continued at end of data sheet.

µMAX is a registered trademark of Maxim Integrated Products, Inc.

+Denotes lead-free package.

*Future product—contact factory for availability.

Ordering Information continued at end of data sheet.