SPRUIW8 November   2020

 

  1.   Trademarks
  2. 1Board Overview
    1. 1.1 Kit Contents
    2. 1.2 Features
    3. 1.3 Specifications
    4. 1.4 Using the F28002x LaunchPad
    5. 1.5 BoosterPacks
    6. 1.6 Hardware Revisions
      1. 1.6.1 Revision A
  3. 2Software Development
    1. 2.1 Software Tools and Packages
    2. 2.2 F28002x LaunchPad Demo Program
    3. 2.3 Programming and Running Other Software on the F28002x LaunchPad
  4. 3Hardware Description
    1. 3.1 Functional Description and Connections
      1. 3.1.1  Microcontroller
      2. 3.1.2  LEDs
      3. 3.1.3  Encoder Connectors
      4. 3.1.4  FSI
      5. 3.1.5  CAN
      6. 3.1.6  CLB
      7. 3.1.7  Boot Modes
      8. 3.1.8  BoosterPack Headers
        1. 3.1.8.1 BoosterPack Sites
      9. 3.1.9  Analog Voltage Reference Header
      10. 3.1.10 Other Headers and Jumpers
        1. 3.1.10.1 USB Isolation Block
        2. 3.1.10.2 BoosterPack Site 2 Power Isolation
        3. 3.1.10.3 Alternate Power
        4. 3.1.10.4 5 V Step-up Converter
    2. 3.2 Debug Interface
      1. 3.2.1 XDS110 Debug Probe
      2. 3.2.2 XDS110 Output
      3. 3.2.3 Virtual COM Port
    3. 3.3 Alternate Routing
      1. 3.3.1 Overview
      2. 3.3.2 UART Routing
      3. 3.3.3 EQEP Routing
      4. 3.3.4 CAN Routing
      5. 3.3.5 FSI Routing
      6. 3.3.6 X1/X2 Routing
      7. 3.3.7 PWM DAC
      8. 3.3.8 Other GPIOs
  5. 4Board Design
    1. 4.1 Schematic
    2. 4.2 PCB Layout
    3. 4.3 BOM
    4. 4.4 LAUNCHXL-F280025C Board Dimensions
  6. 5Frequently Asked Questions
  7. 6References
    1. 6.1 Reference Documents
    2. 6.2 Other TI Components Used in This Design

3.3.7 PWM DAC

The LaunchPad provides two PWM DAC signals at the BoosterPack headers using GPIO22 (BP pin 30) and GPIO23 (BP pin 70) buffered outputs through U10. The intended purpose of the PWM DAC signals are to utilize PWMs of the F28002x device as digitial-to-analog converters (DAC). This method involves low-pass filtering the PWM signal to remove its high-frequency components and ideally leave only the DC component. Please see the Using PWM as a DAC application report for more information.

By default GPIO22 and GPIO23 are connected to the U10 dual buffer through 0 ohm resistors R42 and R43 for the PWM DAC outputs. These resistors can be removed to disconnect the signals from U10 and PWM DAC pins as needed.