SLUSC66E March   2015  – February 2017 UCD3138A


  1. Device Overview
    1. 1.1 Features
    2. 1.2 Applications
    3. 1.3 Description
    4. 1.4 Functional Block Diagram
  2. Device Comparison
    1. 2.1 Product Selection Matrix
  3. Pin Configuration and Functions
    1. 3.1 UCD3138A RGC Package
    2. 3.2 UCD3138A RMH Package
    3. 3.3 UCD3138A RJA Package
  4. Specifications
    1. 4.1 Absolute Maximum Ratings
    2. 4.2 ESD Ratings
    3. 4.3 Recommended Operating Conditions
    4. 4.4 Thermal Information
    5. 4.5 Electrical Characteristics
    6. 4.6 PMBus/SMBus/I2C Timing
    7. 4.7 Peripherals
      1. 4.7.1 Digital Power Peripherals (DPPs)
        1. Front End
        2. DPWM Module
        3. DPWM Events
        4. High Resolution DPWM
        5. Oversampling
        6. DPWM Interrupt Generation
        7. DPWM Interrupt Scaling/Range
        8. DPWM Synchronization
        9. Synchronous Rectifier Dead-Time Optimization Peripheral
    8. 4.8 Typical Temperature Characteristics
  5. Parametric Measurements Information
    1. 5.1 Power-On Reset (POR) and Brown-Out Reset (BOR)
  6. Detailed Description
    1. 6.1 Overview
    2. 6.2 ARM Processor
    3. 6.3 Memory
      1. 6.3.1 CPU Memory Map and interruptions
      2. 6.3.2 Boot ROM
      3. 6.3.3 Customer Boot Program
      4. 6.3.4 Flash Management
    4. 6.4 System Module
      1. 6.4.1 Address Decoder (DEC)
      2. 6.4.2 Memory Management Controller (MMC)
      3. 6.4.3 System Management (SYS)
      4. 6.4.4 Central Interrupt Module (CIM)
    5. 6.5 Feature Description
      1. 6.5.1  Sync FET Ramp and IDE Calculation
      2. 6.5.2  Automatic Mode Switching
        1. Phase Shifted Full Bridge Example
        2. LLC Example
        3. Mechanism for Automatic Mode Switching
      3. 6.5.3  DPWMC, Edge Generation, IntraMux
      4. 6.5.4  Filter
        1. Loop Multiplexer
        2. Fault Multiplexer
      5. 6.5.5  Communication Ports
        1. SCI (UART) Serial Communication Interface
        2. PMBus Interfacte
        3. General Purpose ADC12
        4. Timers
          1. 24-bit PWM Timer
          2. 16-Bit PWM Timers
          3. Watchdog Timer
      6. 6.5.6  Miscellaneous Analog
      7. 6.5.7  Package ID Information
      8. 6.5.8  Brownout
      9. 6.5.9  Global I/O
      10. 6.5.10 Temperature Sensor Control
      11. 6.5.11 I/O Mux Control
      12. 6.5.12 Current Sharing Control
      13. 6.5.13 Temperature Reference
  7. Device Functional Modes
    1. 7.1 Normal Mode
    2. 7.2 DPWM Multiple Output Mode
    3. 7.3 DPWM Resonant Mode
    4. 7.4 Triangular Mode
    5. 7.5 Leading Edge Mode
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. PCMC (Peak Current Mode Control) PSFB (Phase-Shifted Full Bridge) Hardware Configuration Overview
        2. DPWM Initialization for PSFB
      3. 8.2.3 Fixed Signals to Bridge
      4. 8.2.4 Dynamic Signals to Bridge
      5. 8.2.5 System Initialization for PCM
        1. Use of Front Ends and Filters in PSFB
        2. Peak Current Detection
        3. Peak Current Mode (PCM)
      6. 8.2.6 Application Curves
  9. Power Supply Recommendations
    1. 9.1 Power Supply Decoupling and Bulk Capacitors
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. Tools and Documentation
    2. 11.2 Documentation Support
      1. 11.2.1 References
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical Packaging and Orderable Information
    1. 12.1 Packaging Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Device and Documentation Support

Device Support

Development Support

TI offers an extensive line of development tools, including tools to evaluate the performance of the processors, generate code, develop algorithm implementations, and fully integrate and debug software and hardware modules. The tool's support documentation is electronically available within the Code Composer Studio™ Integrated Development Environment (IDE).

The following products support development of the your device device applications:

Software Development Tools: Code Composer Studio™ Integrated Development Environment (IDE): including Editor C/C++/Assembly Code Generation, and Debug plus additional development tools Scalable, Real-Time Foundation Software (DSP/BIOS™), which provides the basic run-time target software needed to support any your device device application.

Hardware Development Tools: Extended Development System (XDS™) Emulator

For a complete listing of development-support tools for the your device platform, visit the Texas Instruments website at For information on pricing and availability, contact the nearest TI field sales office or authorized distributor.

Tools and Documentation

The application firmware for UCD3138A is developed on Texas Instruments Code Composer Studio (CCS) integrated development environment (v6.x recommended).

Device programming, real time debug and monitoring/configuration of key device parameters for certain power topologies are all available through the TI FUSION_DIGITAL_POWER_DESIGNER software.

The FUSION_DIGITAL_POWER_DESIGNER software uses the PMBus protocol to communicate with the device over a serial bus using an interface adaptor known as the USB-TO-GPIO, available as an EVM from Texas Instruments. PMBus-based real-time debug capability is available through the Memory Debugger tool within the Device GUI module of the FUSION_DIGITAL_POWER_DESIGNER GUI, which represents a powerful alternative over traditional JTAG-based approaches.

The software application can also be used to program the devices, with a version of the tool known as FUSION_MFR_GUI optimized for manufacturing environments. The FUSION_MFR_GUI tool supports multiple devices on a board, and includes built-in logging and reporting capabilities.

Programmer manuals are available offering detailed information regarding the application and usage of UCD3138A digital controller:

  1. UCD3138A Digital Power Peripheral Programmer's Manual Key topics covered in this manual include:
    • Digital Pulse Width Modulator (DPWM)
      • Modes of Operation (Normal/Multi/Phase-shift/Resonant and so forth)
      • Automatic Mode Switching
      • DPWMC, Edge Generation and Intra-Mux
    • Front End
      • Analog Front End
      • Error ADC or EADC
      • Front End DAC
      • Ramp Module
      • Successive Approximation Register Module
    • Filter
      • Filter Math
    • Loop Mux
      • Analog Peak Current Mode
      • Constant Current/Constant Power (CCCP)
      • Automatic Cycle Adjustment
    • Fault Mux
      • Analog Comparators
      • Digital Comparators
      • Fault Pin functions
      • DPWM Fault Action
      • Ideal Diode Emulation (IDE), DCM Detection
      • Oscillator Failure Detection
    • Register Map for all of the above peripherals in UCD3138A
  2. UCD3138A Monitoring and Communications Programmer’s Manual
    Key topics covered in this manual include:
    • ADC12
      • Control, Conversion, Sequencing & Averaging
      • Digital Comparators
      • Temperature Sensor
      • PMBUS Addressing
      • Dual Sample and Hold
    • Miscellaneous Analog Controls (Current Sharing, Brown-Out, Clock-Gating)
    • PMBUS Interface
    • General Purpose Input Output (GPIO)
    • Timer Modules
    • PMBus
    • Register Map for all of the above peripherals in UCD3138A
  3. UCD3138A ARM and Digital System Programmer’s Manual
    Key topics covered in this manual include:
    • Boot ROM and Boot Flash
      • BootROM Function
      • Memory Read/Write Functions
      • Checksum Functions
      • Flash Functions
      • Avoiding Program Flash Lock-Up
    • ARM7 Architecture
      • Modes of Operation
      • Hardware/Software Interrupts
      • Instruction Set
      • Dual State Inter-working (Thumb 16-bit Mode/ARM 32-bit Mode)
    • Memory and System Module
      • Address Decoder, DEC (Memory Mapping)
      • Memory Controller (MMC)
      • Central Interrupt Module
    • Register Map for all of the above peripherals in UCD3138A
  4. FUSION_DIGITAL_POWER_DESIGNER for Isolated Power Applications
    • User guide for Designer GUI
    • User guide for Device GUI
    • Firmware Memory Debugger
    • Manufacturing Tool (MFR GUI)

In addition to the tools and documentation described above, for the most up to date information regarding evaluation modules, reference application firmware and application notes/design tips, please visit UCD3138A.

Receiving Notification of Documentation Updates

To receive notification of documentation updates, navigate to the device product folder on In the upper right corner, click on Alert me to register and receive a weekly digest of any product information that has changed. For change details, review the revision history included in any revised document.

Community Resources

The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of Use.

    TI E2E™ Online Community The TI engineer-to-engineer (E2E) community was created to foster collaboration among engineers. At, you can ask questions, share knowledge, explore ideas and help solve problems with fellow engineers.
    Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and contact information for technical support.


Code Composer Studio, Fusion Digital Power, E2E are trademarks of Texas Instruments.

ARM7TDMI-S is a trademark of ARM.

PMBus is a trademark of SMIF, Inc..

All other trademarks are the property of their respective owners.

Electrostatic Discharge Caution


This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.

ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.


    TI Glossary This glossary lists and explains terms, acronyms, and definitions.