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LLC resonant controller with ultra-low power and ultra-quiet standby operation

Inventory: 850

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Packaging information

Package | Pins SOIC (DDB) | 14
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


  • Optimized low power mode and burst mode algorithm
    • Burst mode with Soft-ON and Soft-OFF periods
    • Minimizedaudible noise at no load and standby
    • User option to disable burstmode
    • Opto-coupler low power operation
    • Efficiency performance exceeds DoE Level VI and EU CoC Tier-2 External PowerSupply Standards
  • Hybrid hysteretic control (HHC)
    • Best-in-class transient response
    • Fast exit from burstmode
  • Robust adaptive dead-time control
  • Integrated high-voltage gate driver with 0.6 A source and 1.2 A sink capability
  • Robust capacitive region (ZCS) avoidance scheme
  • Over temperature, output over voltage, input
    under voltage protection, three levels
    of over current protection
  • Integrated high voltage startup function
  • Active X-capacitor discharge function

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The UCC25640xis a fully featured LLC controller with integrated high-voltage gate driver. It has been designedto pair with a PFC controller to provide a complete power system using a minimum of externalcomponents. The resulting power system is designed to meet the most stringent requirements forstandby power without the need for a separate standby power converter.

UCC25640x provides a highly efficient burst mode with soft-on and soft-off periods tominimize audible noise at standby operation. The burst power level and hysteresis are programmable,simplifying the optimization of efficiency and burst mode operation. Burst mode can also bedisabled through pin configuration. UCC25640x uses hybrid hysteretic control to provide best inclass line and load transient response.

UCC25640x includes a range of features designed to make LLC converter operation wellcontrolled and protected. It can be used with UCC28056 or UCC28064A PFC controllers, along withUCC24624 synchronous rectifier controller to offer a complete power supply solution.

Qty Price
1-99 $1.81
100-249 $1.50
250-999 $1.08
1,000+ $0.81

Alternative carriers

Part number UCC256403DDBR
Package qty | Carrier 2,500 | LARGE T&R
Custom reel may be available
Inventory 1,695
Qty | Price (USD) 1ku | $0.70