ISL6745A

Improved Bridge Controller with Precision Dead Time Control

Product Status: Mass Production

OVERVIEW

The ISL6745A is a low-cost, double-ended, voltage-mode PWM controller designed for half-bridge and full-bridge power supplies and line-regulated bus converters. It provides precise control of switching frequency, adjustable soft-start, and overcurrent shutdown. In addition, the ISL6745A allows for accurate adjustment of MOSFET non-overlap time ("dead time") with dead times as low as 35ns, allowing power engineers to optimize the efficiency of open-loop bus converters. The ISL6745A also includes a control voltage input for closed-loop PWM and line voltage feed-forward functions. The ISL6745A is identical to the ISL6745, but is optimized for higher noise environments.

Low start-up and operating currents allow for easy biasing in both AC/DC and DC/DC applications. This advanced BiCMOS design also features adjustable switching frequency up to 1MHz, 1A FET drivers, and very low propagation delays for a fast response to overcurrent faults. The ISL6745A is available in a space-saving 10 Ld MSOP package and is assured to meet rated specifications across a wide -40°C to +105°C temperature range.

KEY FEATURES

  • Precision duty cycle and deadtime control
  • 100µA start-up current
  • Adjustable delayed overcurrent shutdown and restart
  • Adjustable oscillator frequency up to 2MHz
  • 1A MOSFET gate drivers
  • Adjustable soft-start
  • Internal over-temperature protection
  • 35ns control to output propagation delay
  • Small size and minimal external component count
  • Input undervoltage protection
  • Pb-free (RoHS compliant)

BLOCK DIAGRAM

 Block Diagram

PARAMETRICS

Parameters
ISL6745A
Basic Information
Production Status
Mass Production
Topology
Double-Ended
Topology Characteristic
Half-Bridge or Full Bridge (Telecom) Hard SW
Control Mode
Voltage Mode
UVLO Rising (V)
6.3
UVLO Falling (V)
5.7
VBIAS (max) (V)
20
No-Load Operating Current
7.5 mA
# of PWM Outputs
2
Max Duty Cycle (%)
100
Qualification Level
Standard
Can Sample
YES
Temperature Range
-40 to +105

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