SLUSAP2J March   2012  – November 2021 UCD3138

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Functional Block Diagram
  5. 5 Revision History
  6. 6 Device Comparison Table
    1. 6.1 Product Family Comparison
    2. 6.2 Product Selection Matrix
  7. 7 Pin Configuration and Functions
    1. 7.1 UCD3138RGC 64 QFN Pin Attributes
    2. 7.2 UCD3138RHA, UCD3138RMH and UCD3138RJA Pin Attributes
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing and Switching Characteristics
    7. 8.7 Power Supply Sequencing
    8. 8.8 Peripherals
      1. 8.8.1 Digital Power Peripherals (DPPs)
        1. 8.8.1.1 Front End
        2. 8.8.1.2 DPWM Module
        3. 8.8.1.3 DPWM Events
        4. 8.8.1.4 High Resolution DPWM
        5. 8.8.1.5 Oversampling
        6. 8.8.1.6 DPWM Interrupt Generation
        7. 8.8.1.7 DPWM Interrupt Scaling/Range
    9. 8.9 Typical Temperature Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 ARM Processor
    3. 9.3 Memory
      1. 9.3.1 CPU Memory Map and Interrupts
      2. 9.3.2 Boot ROM
      3. 9.3.3 Customer Boot Program
      4. 9.3.4 Flash Management
    4. 9.4 System Module
      1. 9.4.1 Address Decoder (DEC)
      2. 9.4.2 Memory Management Controller (MMC)
      3. 9.4.3 System Management (SYS)
      4. 9.4.4 Central Interrupt Module (CIM)
    5. 9.5 Feature Description
      1. 9.5.1  Sync FET Ramp and IDE Calculation
      2. 9.5.2  Automatic Mode Switching
        1. 9.5.2.1 Phase Shifted Full Bridge Example
        2. 9.5.2.2 LLC Example
        3. 9.5.2.3 Mechanism for Automatic Mode Switching
      3. 9.5.3  DPWMC, Edge Generation, IntraMux
      4. 9.5.4  Filter
        1. 9.5.4.1 Loop Multiplexer
        2. 9.5.4.2 Fault Multiplexer
      5. 9.5.5  Communication Ports
        1. 9.5.5.1 SCI (UART) Serial Communication Interface
        2. 9.5.5.2 PMBUS
        3. 9.5.5.3 General Purpose ADC12
        4. 9.5.5.4 Timers
          1. 9.5.5.4.1 24-bit PWM Timer
          2. 9.5.5.4.2 16-Bit PWM Timers
          3. 9.5.5.4.3 Watchdog Timer
      6. 9.5.6  Miscellaneous Analog
      7. 9.5.7  Package ID Information
      8. 9.5.8  Brownout
      9. 9.5.9  Global I/O
      10. 9.5.10 Temperature Sensor Control
      11. 9.5.11 I/O Mux Control
      12. 9.5.12 Current Sharing Control
      13. 9.5.13 Temperature Reference
    6. 9.6 Device Functional Modes
      1. 9.6.1 Normal Mode
      2. 9.6.2 Phase Shifting
      3. 9.6.3 DPWM Multiple Output Mode
      4. 9.6.4 DPWM Resonant Mode
      5. 9.6.5 Triangular Mode
      6. 9.6.6 Leading Edge Mode
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 PCMC (Peak Current Mode Control) PSFB (Phase Shifted Full Bridge) Hardware Configuration Overview
        2. 10.2.2.2 DPWM Initialization for PSFB
        3. 10.2.2.3 DPWM Synchronization
        4. 10.2.2.4 Fixed Signals to Bridge
        5. 10.2.2.5 Dynamic Signals to Bridge
        6. 10.2.2.6 System Initialization for PCM
          1. 10.2.2.6.1 Use of Front Ends and Filters in PSFB
          2. 10.2.2.6.2 Peak Current Detection
          3. 10.2.2.6.3 Peak Current Mode (PCM)
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
    1. 11.1 Introduction To Power Supply and Layout Recommendations
    2. 11.2 3.3-V Supply Pins
    3. 11.3 Recommendation for V33 Ramp up Slew Rate for UCD3138 and UCD3138064
    4. 11.4 Recommendation for RC Time Constant of RESET Pin for UCD3138 and UCD3138064
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 EMI and EMC Mitigation Guidelines
      2. 12.1.2 BP18 Pin
      3. 12.1.3 Additional Bias Guidelines
      4. 12.1.4 UCD3138 Pin Connection Recommendation
        1. 12.1.4.1 Current Amplifier With EADC Connection
        2. 12.1.4.2 DPWM Synchronization
        3. 12.1.4.3 GPIOS
        4. 12.1.4.4 DPWM PINS
        5. 12.1.4.5 EAP and EAN Pins
        6. 12.1.4.6 ADC Pins
      5. 12.1.5 UART Communication Port
      6. 12.1.6 Special Considerations
    2. 12.2 Layout Example
      1. 12.2.1 UCD3138 and UCD3138064 40 Pin
      2. 12.2.2 UCD3138 and UCD3138064 64 Pin
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Code Composer Studio
      2. 13.1.2 Tools and Documentation
    2. 13.2 Documentation Support
      1. 13.2.1 References
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical Packaging and Orderable Information
    1. 14.1 Packaging Information

Package Options

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

8.8.1.1 Front End

Figure 8-4 shows the block diagram of the front end module. It consists of a differential amplifier, an adjustable gain error amplifier, a high speed flash analog to digital converter (EADC), digital averaging filters and a precision high resolution set point DAC reference. The programmable gain amplifier in concert with the EADC and the adjustable digital gain on the EADC output work together to provide 9 bits of range with 6 bits of resolution on the EADC output. The output of the Front End module is a 9-bit sign extended result with a gain of 1 LSB / mV. Depending on the value of AFE selected, the resolution of this output could be either 1, 2, 4 or 8 LSBs. In addition Front End 0 has the ability to automatically select the AFE value such that the minimum resolution is maintained that still allows the voltage to fit within the range of the measurement. The EADC control logic receives the sample request from the DPWM module for initiating an EADC conversion. EADC control circuitry captures the EADC-9-bit-code and strobes the digital compensator for processing of the representative error. The set point DAC has 10 bits with an additional 4 bits of dithering resulting in an effective resolution of 14 bits. This DAC can be driven from a variety of sources to facilitate things like soft start, nested loops, and so forth. Some additional features include the ability to change the polarity of the error measurement and an absolute value mode which automatically adds the DAC value to the error.

It is possible to operate the controller in a peak current mode control configuration; front-end 2 is recommended for implementing peak current mode control. In this mode topologies like the phase shifted full bridge converter can be controlled to maintain transformer flux balance. The internal DAC can be ramped at a synchronously controlled slew rate to achieve a programmable slope compensation. This eliminates the sub-harmonic oscillation as well as improves input voltage feed-forward performance. A0 is a unity gain buffer used to isolate the peak current mode comparator. The offset of this buffer is specified in Section 8.5.

GUID-F9EF0C1D-3AA3-418A-B93C-9FE81B991B48-low.gifFigure 8-4 Input Stage of EADC Module
GUID-070D9C51-2871-43F9-99B1-546C80743E6F-low.gifFigure 8-5 Front End Module (Front End 2 Recommended for Peak Current Mode Control)