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Phase-shifted full-bridge controller for wide input voltage range

Availability: 1,924


Package | PIN: TSSOP (PW) | 24
Temp: Q (-40 to 125)
Carrier: Cut Tape
Qty Price
1-9 $6.98
10-24 $6.28
25-99 $5.87
100-249 $5.26
250-499 $4.91
500-749 $4.27
750-999 $3.70
1000+ $3.62


  • Enhanced Zero-Voltage Switching (ZVS) Range
  • Direct Synchronous Rectifier (SR) Control
  • Light-Load Efficiency Management Including:
    • Burst ModeOperation
    • Discontinuous Conduction Mode (DCM), Dynamic SR On/Off Control WithProgrammable Threshold
    • Programmable AdaptiveDelay
  • 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 1 MHz With Bidirectional Synchronization
  • (±3%) Cycle-by-Cycle Current Limit Protection With Hiccup Mode Support
  • 150-µA Start-Up Current
  • VDD Undervoltage Lockout
  • Wide Temperature Range: –40°C to +125°C

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Texas Instruments  UCC28951PWT

The UCC28951 device is an enhanced version of theUCC28950. It is a fullycompatible drop-in replacement for the UCC28950. Refer to application note SLUA853 to determine which controller to use. The UCC28951 uses advanced control of the full-bridge in addition to active control of thesynchronous rectifier (SR) output stage.

Programmable delays ensure ZVS operation over a wide range of operating conditions, whilethe load current naturally tunes the switching delays of the secondary-side synchronousrectifiers(SR). This functionality maximizes overall system efficiency.

The UCC28951 has many light-load management features includingburst-mode operation and dynamic SR ON and OFF control during transition into and out ofdiscontinuous current mode (DCM) operation. The device operates in current-mode or voltage-modecontrol. The switching frequency can be programmed up to 1 MHz. The device has protection featuresincluding cycle-by-cycle current limit, UVLO, and thermal shutdown.

The 24-pin, TSSOP package complies with RoHS requirements .