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Green phase-shifted full-bridge controller with SR control for Wide input voltage Range

Inventory: 2,840

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Packaging information

Package | Pins TSSOP (PW) | 24
Operating temperature range (℃) Q (-40 to 125)
Package qty | Carrier: 250 | SMALL T&R
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Quality information

RoHS Yes
Lead finish / Ball material NIPDAU
MSL rating / Peak reflow Level-2-260C-1 YEAR
Material content View
DPPM / MTBF / Fit rate View
Qualification summary View
Ongoing reliability monitoring View
Device marking View


  • 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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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 .

Qty Price
1-99 $4.66
100-249 $3.80
250-999 $2.98
1,000+ $2.53