SBAU439 January   2024

 

  1.   1
  2.   Description
  3.   Get Started
  4.   Features
  5.   Applications
  6.   6
  7. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  8. 2Hardware
    1. 2.1 Analog Interface
      1. 2.1.1 ADC Channel Inputs
        1. 2.1.1.1 High-bandwidth, Fully-Differential Circuit: THS4551
        2. 2.1.1.2 Precision, High-CMRR Circuit: PGA855
      2. 2.1.2 Voltage Reference
    2. 2.2 Power Supplies
      1. 2.2.1 USB Power and When to Power the Board Externally
    3. 2.3 Digital Interface and Clock Inputs
      1. 2.3.1 Digital Interface Connections
      2. 2.3.2 Clock Select
    4. 2.4 ADS9227EVM Quick Start Guide
  9. 3Software
    1. 3.1 ADS9227EVM Software Reference
      1. 3.1.1 ADS9227EVM-GUI Software Installation
      2. 3.1.2 USB Driver Installation
      3. 3.1.3 Using the CONFIG Tab
      4. 3.1.4 Using the Capture Tab
      5. 3.1.5 Using the INL/DNL Tool
      6. 3.1.6 Using the Histogram Tab
  10. 4Hardware Design Files
    1. 4.1 Schematics
    2. 4.2 PCB Layout
    3. 4.3 Bill of Materials (BOM)
  11. 5Additional Information
    1.     Trademarks
  12. 6Related Documentation

2.2.1 USB Power and When to Power the Board Externally

As discussed in Section 2.4, the USB-C connector is able to provide power to the TSWDC155EVM and ADS9227EVM using the default configuration. The combined peak current consumption reaches 600 mA (typical) during the ADC conversion process and 520 mA RMS (typical) after the ADS9227EVM is initialized in the GUI, as described in Section 3.1.3.

The TWDC155EVM is a high-power SuperSpeed (USB 3.0) device. This means a PC supplies up to 900 mA from a compliant USB 3.0 port. However, many PC USB port configurations allow much less than this limit depending on the unit load handshake process, usually resulting from other devices on the bus. Tripping the current limit on a USB can result in cutting power to the USB port, excessive power dissipation or heating, depending on the PC port configuration. As a result, TI highly recommends to consider switching to an externally powered ADS9227EVM and/or TSWDC155EVM if:

  • Only USB 1.0 or USB 2.0 ports are available.
  • There are multiple devices connected to the PC by USB at the same time.
  • The USB 3.0 port configuration for the PC is unknown.

To switch to the external power configuration on the ADS9227EVM, move the jumper on J18 to the EXT_PWR position and use the J17 terminal block to provide the required 5.2-V to 5.5-V supply. To switch to the external power configuration on TSWDC155EVM, move the jumper on J2 to the 5 V (external) position and use the J10 terminal block or barrel jack connector to provide the required 5-V supply.

USB hubs can cause possible device enumeration issues and are not recommended when communicating through the TSWDC155EVM.