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Texas Instruments UCC28951/UCC28951-Q1 Full Bridge Controllers

Texas Instruments UCC28951/UCC28951-Q1 Full Bridge Controllers are enhanced phase-shifted full-bridge controllers built upon TI's industry-standard UCC28950. These controllers are fully compatible drop-in replacements for the UCC28950. The UCC28951/UCC28951-Q1 uses advanced control of the full-bridge and active control of the synchronous rectifier (SR) output stage. Programmable delays ensure ZVS operation over a wide range of operating conditions. This delay is done while the load current naturally tunes the switching delays of the secondary-side SRs. This functionality maximizes overall system efficiency.

The UCC28951/UCC28951-Q1 has many light-load management features, including burst-mode operation and dynamic SR ON and OFF control during the transition into and out of discontinuous current mode (DCM) operation. The device operates in current-mode or voltage-mode control. The switching frequency can be programmed up to 1MHz. The device has protection features, including a cycle-by-cycle current limit, UVLO, and thermal shutdown. The Texas Instruments UCC28951-Q1 devices are AEC-Q100 qualified for automotive applications.

Features

  • Enhanced Zero-Voltage Switching (ZVS) range
  • Direct Synchronous Rectifier (SR) control
  • Light-load efficiency management including
    • Burst mode operation
    • Discontinuous Conduction Mode (DCM), dynamic SR on/off control with programmable threshold
    • Programmable adaptive delay
  • Average or peak-current mode control with programmable slope compensation and voltage-mode control
  • Closed-loop soft-start and enable function
  • Programmable switching frequency up to 1MHz with bidirectional synchronization
  • (±3%) cycle-by-cycle current limit protection with hiccup mode support
  • 150µA start-up current
  • VDD undervoltage lockout
  • –40°C to +125°C wide temperature range

Applications

  • Phase-shifted full-bridge converters
  • Server power supply
  • Industrial power systems
  • High-density power architectures

Datasheets

Functional Block Diagram

Block Diagram - Texas Instruments UCC28951/UCC28951-Q1 Full Bridge Controllers
Published: 2017-05-12 | Updated: 2022-05-06