SLVUDA2 July   2025

 

  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.   General Texas Instruments High Voltage Evaluation (TI HV EVM) User Safety Guidelines
  9. 2Hardware
    1. 2.1 Power Requirements
    2. 2.2 Test Points
    3. 2.3 Setup
      1. 2.3.1 Reference Voltage
        1. 2.3.1.1 Configuration 1: REFA and REFB = GND
        2. 2.3.1.2 Configuration 2: OPA CH A Bias REFA and REFB
        3. 2.3.1.3 Configuration 3: REFA and REFB Bias Independently
      2. 2.3.2 Current Sensing
      3. 2.3.3 Input Filtering
      4. 2.3.4 Output Load
    4. 2.4 Best Practices
  10. 3Hardware Design Files
    1. 3.1 Schematic
    2. 3.2 PCB Layouts
    3. 3.3 Bill of Materials (BOM)
  11. 4Additional Information
    1. 4.1 Trademarks
    2. 4.2 Related Documentation

2.3.1 Reference Voltage

The EVM has an optional reference buffer footprint to allow the reference pin to be biased to different voltage potentials. Headers J12, J13, and J14 allow flexibility for the reference circuitry to drive the reference pins (REFA and REFB) together or independently with the external reference buffer circuitry. Information on the different configuration options are shown in Table 2-3. By default, this circuit is left unpopulated and the headers set up the device for both REF pins to be grounded (see Section 2.3.1.1).

For options on how to supply power to the reference buffer circuit, see Section 2.1.

The OPA4H014-SEP was selected for the reference buffer (U2) in the schematic because of compatibility with space applications. Most quad channel operational amplifier in TSSOP-14 package can be used as an alternative when using the reference circuit. Space-grade operational amplifier recommendations can be found through this link on TI.com.

The reference voltage can be biased in multiple configurations, modifying the transfer function. Common configurations and examples with setup required are outlined from Section 2.3.1.1 to Section 2.3.1.3.

Table 2-3 Header Configurations for Reference Pins (REFA and REFB)
HEADER NAME SETTING DESCRIPTION
J12 Closed Short REFA and REFB pin together
Open REFA and REFB pin connect separately
J13 Closed (REFA to OPA) REFA is connected to output of reference buffer Ch A
Closed (REFA to GND) REFA is connected to GND
Open REFA is left floating. Pin can be driven externally through TP8.
J14 Closed (REFB to OPB) REFB is connected to output of reference buffer Ch B
Closed (REFB to GND) REFB is connected to GND
Open REFB is left floating. Pin can be driven externally through TP9.