UCD3138 LLC Half Bridge Firmware
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UCD3138 LLC Half bridge Firmware




UCD3138 Resonant LLC Programmer quickly gets a designer through evaluation to production in power supply designs based on a resonant LLC topology by providing  firmware with ZCS protection and mode switching capability to achieve high efficiency across wider operating conditions. The sunflower feature (UCC7138) in the firmware provides advanced synchronous rectification control.

The resonant LLC topology reduces switching losses and EMI while offering great efficiency through a half-bridge converter with zero-voltage switching on the primary side of the converter. It scales to high power output levels and can operate well with a wide range of input voltages.


This firmware comes with native support for following features:

  • Dynamic mode switching between frequencies to pulse width modulation
  • Cycle by cycle current limit with duty cycle matching
  • Short-circuit constant current operation
  • Overcurrent/overload protection
  • Current sharing
  • Optimized dead time using UCD7138 (sunflower)
  • Accurate and adaptable primary-to-secondary timing control
  • Fully flexible dead time control between all MOSFETs control signals
  • Hysteretic burst mode (based on voltage mode control) for light load efficiency
  • Constant current, constant power control under overload
  • ZCS prevention and protection
  • Optimized loop coefficients for different operating regions
  • PMBus 1.2 with 400 KHz for telemetry operations

 What’s Included:

  • Application examples
  • EVM and firmware collaterals

Software development (2)

Name Part Number Software Type
Digital Power Software  FUSION_DIGITAL_POWER_DESIGNER  Application software & framework 
Code Composer Studio (CCS) Integrated Development Environment (IDE)  CCSTUDIO  IDE, configuration, compiler or debugger 

TI Devices (7)

Part Number Name Product Family
UCD3138  Highly Integrated Digital Controller for Isolated Power with 3 Feedback Loops and 8 DPWM Outputs  Digital power ICs 
UCD3138064  Highly-Integrated Digital Controller for Isolated Power with 64kB Memory  Digital power ICs 
UCD3138064A  Highly Integrated Digital Controller for Isolated Power  Digital power ICs 
UCD3138128  Highly-Integrated Digital Controller for Isolated Power  Digital power ICs 
UCD3138128A  Highly-Integrated Digital Controller For Isolated Power  Digital power ICs 
UCD3138A  UCD3138A Highly Integrated Digital Controller for Isolated Power  Digital power ICs 
UCD3138A64  Highly-Integrated Digital Controller for Isolated Power  Digital power ICs 

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