ISL6740A Datasheet, PDF (1/15 Pages) Intersil Corporation – Flexible Double-Ended Voltage-Mode PWM Controller with Voltage Feed Forward

®
Data Sheet
February 7, 2005
ISL6740A
FN9195.0
Flexible Double-Ended Voltage-Mode
PWM Controller with Voltage Feed
Forward
The ISL6740A is an enhanced ISL6740 PWM controller
featuring built-in voltage feed forward functionality. It is pin
and feature compatible with the ISL6740 double-ended
pulse width modulating (PWM) voltage-mode controller,
allowing easy drop-in replacement on existing designs.
Voltage feed forward compensates for input voltage variation
without intervention of the feedback control loop. It is
particularly useful in unregulated bus converters and DC
transformers where wide input voltage variation would
otherwise result in large output voltage swings.
In addition to voltage feed forward compensation, the
ISL6740A features an extremely flexible oscillator that
allows precise control of frequency, duty cycle, and
deadtime. Deadtimes of under 40ns are easily achievable.
This advanced BiCMOS design features low operating
current, adjustable switching frequency up to 1MHz,
adjustable soft-start, internal and external over temperature
protection, fault annunciation, and a bidirectional SYNC
signal that allows the oscillator to be locked to paralleled
units or to an external clock for noise sensitive applications.
Ordering Information
TEMP. RANGE
PART NUMBER
(°C)
PACKAGE
PKG.
DWG. #
ISL6740AIVZA
(Note)
-40 to 105 16 Ld TSSOP M16.173
(Pb-free)
Add -T suffix to part number for tape and reel packaging
NOTE: Intersil Pb-free products employ special Pb-free material
sets; molding compounds/die attach materials and 100% matte tin
plate termination finish, which are RoHS compliant and compatible
with both SnPb and Pb-free soldering operations. Intersil Pb-free
products are MSL classified at Pb-free peak reflow temperatures that
meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
Features
• Input Voltage Feed Forward Compensation
• Precision Duty Cycle and Deadtime Control
• Adjustable Delayed Overcurrent Shutdown and Re-Start
• Adjustable Short Circuit Shutdown and Re-Start
• Adjustable Oscillator Frequency Up to 2MHz
• Bidirectional Synchronization
• Adjustable Input Undervoltage Lockout/Inhibit
• Tight Tolerance Voltage Reference Over Line, Load, and
Temperature
• Adjustable Soft-Start
• Fault Signal
• 95µA Startup Current
• Internal Over Temperature Protection
• System Over Temperature Protection Using a Thermistor
or Sensor
• Pb-free and ELV, WEEE, RoHS Compliant
Applications
• Telecom and Datacom Power
• Wireless Base Station Power
• File Server Power
• Industrial Power Systems
• DC Transformers and Bus Converters
Pinout
ISL6740A (TSSOP)
TOP VIEW
OUTA 1
GND 2
SCSET 3
C_T 4
SYNC 5
CS 6
V_ERROR 7
UV/FF 8
16 OUTB
15 V_REF
14 V_DD
13 R_TD
12 R_TC
11 OTS
10 FAULT
9 SS
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-352-6832 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2005. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.