1

10

11

12

13

14

15

16

17

18

19

7

7

7

7

7

7

7

7

7

20

2

3

4

5

6

7

8

9

UCC3895

EAN

EAP

EAOUT

RAMP

REF

GND

SYNC

CT

RT

DELAB

DELCD

ADS

CS

OUTD

OUTC

VCC

PGND

OUTB

OUTA

SS/DISB

Q1

D

B

A

C

UCC1895, UCC2895, UCC3895

www.ti.com

SLUS157P – DECEMBER 1999 – REVISED JUNE 2013

BiCMOS Advanced Phase-Shift PWM Controller

Check for Samples: UCC1895, UCC2895, UCC3895

1

FEATURES

DESCRIPTION

The UCC3895 is a phase-shift PWM controller that

•

Programmable-Output Turnon Delay

implements control of a full-bridge power stage by

•

Adaptive Delay Set

phase shifting the switching of one half-bridge with

•

Bidirectional Oscillator Synchronization

respect to the other. The device allows constant

frequency pulse-width modulation in conjunction with

•

Voltage-Mode, Peak Current-Mode, or Average

resonant zero-voltage switching to provide high

Current-Mode Control

efficiency at high frequencies. The part is used either

•

Programmable Softstart, Softstop and Chip

as a voltage-mode or current-mode controller.

Disable via a Single Pin

While the UCC3895 maintains the functionality of the

•

0% to 100% Duty-Cycle Control

UC3875/6/7/8 family and UC3879, it improves on that

•

7-MHz Error Amplifier

controller family with additional features such as

enhanced control logic, adaptive delay set, and

•

Operation to 1 MHz

shutdown capability. Because the device is built using

•

Typical 5-mA Operating Current at 500 kHz

the BCDMOS process, it operates with dramatically

•

Very Low 150-

μA Current During UVLO

less supply current than it’s bipolar counterparts. The

UCC3895 operates with a maximum clock frequency

APPLICATIONS

of 1 MHz.

•

Phase-Shifted Full-Bridge Converters

•

Off-Line, Telecom, Datacom and Servers

•

Distributed Power Architecture

•

High-Density Power Modules

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Copyright © 1999–2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.