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

2.3.1.3 Configuration 3: REFA and REFB Bias Independently

Figure 2-6 shows circuit for Configuration 3 and Table 2-6 outlines the header pin settings.

This use case sets the reference voltage for REFA and REFB independently. REFA is set by channel A of the external reference buffer (U2) and REFB is set by channel B. The corresponding transfer function becomes Equation 3. The buffer circuitry must be populated and at a minimum, the following components needs to be added: U2, R7, R10, R12, R13.

Two separate reference voltages can be biased to REFA and REFB by either applying a voltage to TP12 and TP15 or changing the resistor ratio on the input voltage divider (R6/R8 and R9/R11). Do not connect both an external voltage source and populate the resistor divider network.

Equation 3. V O U T =   ( + I N ) - ( - I N ) + 20 × R E F A - 19 × R E F B
Table 2-6 Header Pins for Configuration 3
HEADER NAME SETTING
J12 Closed
J13 Closed (REFA to OPA)
J14 Closed (REFB to OPB)
INA1H94EVM REFA and REFB Bias Independently Figure 2-7 REFA and REFB Bias Independently