The LM5046SQ/NOPB PWM controller contains all of the features necessary to implement a phase-shifted full-bridge topology power converter using either current mode or voltage mode control. This device is intended to operate on the primary side of an isolated DC-DC converter with input voltage up to 100 V. This highly integrated controller-driver provides dual 2-A high- and low-side gate drivers for the four external bridge MOSFETs, plus control signals for the secondary-side synchronous rectifier MOSFETs. External resistors program the dead-time to enable zero-volt switching of the primary FETs. Intelligent startup of the synchronous rectifiers allows monotonic turnon of the power converter even with prebias load conditions. Additional features include cycle-by-cycle current limiting, hiccup mode restart, programmable soft-start, synchronous rectifier soft-start, and a 2-MHz capable oscillator with synchronization capability and thermal shutdown.
Feature
- Highest Integration Controller for Small Form Factor, High-Density Power Converters
- High-Voltage Start-Up Regulator
- Intelligent Sync Rectifier Start-Up Allows Linear Turn-on into Prebiased Loads
- Synchronous Rectifiers Disabled in UVLO Mode and Hiccup Mode
- Two Independent, Programmable Dead-Time Adjustments to Enable Zero-Volt Switching
- Four High-Current 2-A Bridge Gate Drivers
- Wide-Bandwidth Opto-Coupler Interface
- Configurable for Either Current Mode or Voltage Mode Control
- Dual-Mode Overcurrent Protection
- Resistor Programmed 2-MHz Oscillator
- Programmable Line UVLO and OVP
The LM5046 PWM controller contains all of the features necessary to implement a phase-shifted full-bridge topology power converter using either current mode or voltage mode control. This device is intended to operate on the primary side of an isolated DC-DC converter with input voltage up to 100 V. This highly integrated controller-driver provides dual 2-A high- and low-side gate drivers for the four external bridge MOSFETs, plus control signals for the secondary-side synchronous rectifier MOSFETs. External resistors program the dead-time to enable zero-volt switching of the primary FETs. Intelligent startup of the synchronous rectifiers allows monotonic turnon of the power converter even with prebias load conditions. Additional features include cycle-by-cycle current limiting, hiccup mode restart, programmable soft-start, synchronous rectifier soft-start, and a 2-MHz capable oscillator with synchronization capability and thermal shutdown.
