SLUS652E March   2005  – April 2020 UCD8220

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1. 3.1 UCD8220 Typical Simplified Push-Pull Converter Application Schematic
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 CLK Input Time-Domain Digital Pulse Train
      2. 7.3.2 Current Sensing and Protection
      3. 7.3.3 Handshaking
      4. 7.3.4 Driver Output
      5. 7.3.5 Source and Sink Capabilities During Miller Plateau
      6. 7.3.6 Drive Current and Power Requirements
      7. 7.3.7 Clearing the Current-Limit Flag (CLF)
    4. 7.4 Device Functional Modes
  8. 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. 8.2.2.1 Selecting the ISET Resistor for Voltage Mode Control
        2. 8.2.2.2 Selecting the ISET Resistor for Voltage Mode Control with Voltage Feed Forward
        3. 8.2.2.3 Selecting the ISET Resistor for Peak Current Mode Control with Internal Slope Compensation
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • PWP|16
Thermal pad, mechanical data (Package|Pins)
Orderable Information

3 Description

The UCD8220 analog pulse-width modulator (PWM) device is used in digitally managed power supplies using a microcontroller or the TMS320 DSP family.

The UCD8220 device is a double-ended PWM controller configured with push-pull drive logic.

Systems using the UCD8220 device close the PWM feedback loop with traditional analog methods, but the UCD8220 controller includes circuitry to interpret a time-domain digital pulse train. The pulse train contains the operating frequency and maximum duty cycle limit which are used to control the power supply operation. The device circuitry eases implementation of a converter with high level control features without the added complexity or possible PWM resolution limitations of closing the control loop in the discrete time domain.

The UCD8220 device can be configured for either peak current mode or voltage mode control. The device provides a programmable current-limit function and a digital output current-limit flag which can be monitored by the host controller to set the current limit operation. For fast switching speeds, the output stage uses the TrueDrive output circuit architecture, which delivers rated current of ±4-A into the gate of a MOSFET. Finally the device also includes a 3.3-V, 10-mA linear regulator to provide power to the digital controller or act as a reference in the system.

The UCD8220 controller is compatible with the standard 3.3-V I/O ports of UCD9K digital power controllers, DSPs, microcontrollers, or ASICs and is offered in the PowerPAD™ integrated circuit package HTSSOP.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
UCD8220 HTSSOP (16) 5.00 mm × 4.40 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

3.1 UCD8220 Typical Simplified Push-Pull Converter Application Schematic

UCD8220 d8220_hbcir_lus652.gif