New Industry Products

TI Green Phase-Shifted Full-Bridge Controller Includes Synchronous Rectifier Output Control

February 24, 2010 by Jeff Shepard

Texas Instruments Inc. (TI) introduced a phase-shifted full-bridge PWM controller with synchronous MOSFET control outputs and light load power management. The UCC28950 can achieve efficiencies above 90% from light load to full load, enabling it to meet 90+ Climate Savers® efficiency standards. The device features an adaptive zero voltage switching (ZVS) control scheme with a 10:1 range that can maintain ZVS over wide input voltage variations or output load swings. The wider ZVS operational range saves energy consumption across a broader power output range.

The UCC28950 also has optimized adaptive control for the output synchronous rectifiers including on/off control to optimize efficiency at lighter loads. The UCC28950 is designed for applications like high-power, high-density power supplies; server and telecom power supplies; industrial power systems; solar inverters; electric vehicles; and dc motor drives.

Key features and benefits of the UCC28950 include: synchronous rectifier outputs optimize timing to minimize body diode conduction losses from typical propagation delays, which ensure high efficiency; advanced power management functions that change operational modes under different start-up or load conditions and a burst mode that is said to improve light load or no load efficiency by as much as 70% compared to non-green mode solutions; the programmable ramp compensation allows for current or voltage mode control, adding system flexibility; a soft start with enable function allows the UCC28950 to initialize start-up by higher level system control; and sync in and sync out function with 90 degrees phase shift for interleaved operation of two parallel power supplies reduces input and output ripple current by 50 to 100%.

The UCC28950 is available now in a TSSOP-24 package and is priced at $4.25 in quantities of 1,000.