UCC1895, UCC2895, UCC3895
www.ti.com
SLUS157P – DECEMBER 1999 – REVISED JUNE 2013
BiCMOS Advanced Phase-Shift PWM Controller
Check for Samples: UCC1895, UCC2895, UCC3895
FEATURES
DESCRIPTION
•
•
•
•
The UCC3895 is a phase-shift PWM controller that
implements control of a full-bridge power stage by
phase shifting the switching of one half-bridge with
respect to the other. The device allows constant
frequency pulse-width modulation in conjunction with
resonant zero-voltage switching to provide high
efficiency at high frequencies. The part is used either
as a voltage-mode or current-mode controller.
1
•
•
•
•
•
•
Programmable-Output Turnon Delay
Adaptive Delay Set
Bidirectional Oscillator Synchronization
Voltage-Mode, Peak Current-Mode, or Average
Current-Mode Control
Programmable Softstart, Softstop and Chip
Disable via a Single Pin
0% to 100% Duty-Cycle Control
7-MHz Error Amplifier
Operation to 1 MHz
Typical 5-mA Operating Current at 500 kHz
Very Low 150-μA Current During UVLO
APPLICATIONS
•
•
•
•
While the UCC3895 maintains the functionality of the
UC3875/6/7/8 family and UC3879, it improves on that
controller family with additional features such as
enhanced control logic, adaptive delay set, and
shutdown capability. Because the device is built using
the BCDMOS process, it operates with dramatically
less supply current than it’s bipolar counterparts. The
UCC3895 operates with a maximum clock frequency
of 1 MHz.
Phase-Shifted Full-Bridge Converters
Off-Line, Telecom, Datacom and Servers
Distributed Power Architecture
High-Density Power Modules
UCC3895
1
EAN
2
EAOUT
3
Q1
EAP
20
7
SS/DISB
19
RAMP
OUTA
18
4
REF
OUTB
17
5
GND
PGND
16
6
SYNC
VCC
15
7
CT
OUTC
14
VOUT
A
VIN
VBIAS
B
8
RT
OUTD
9
CS
10
12
DELCD
ADS
D
13
DELAB
C
11
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.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 1999–2013, Texas Instruments Incorporated
