SBOU268 November   2021 OPA593

 

  1.   Trademarks
  2. 1Overview
    1. 1.1 Getting Started
      1. 1.1.1 Related Documentation From Texas Instruments
    2. 1.2 High-Voltage Warning and Safe Use
    3. 1.3 Electrostatic Discharge Caution
  3. 2Operation
    1. 2.1 Jumper Blocks, Jacks, and Test Points
    2. 2.2 Inputs
    3. 2.3 Outputs
    4. 2.4 Enable or Disable
    5. 2.5 Status Flags
      1. 2.5.1 Circuit Protection
  4. 3Application Circuits
    1. 3.1 Setting Dual-Supply or Single-Supply Operation
      1. 3.1.1 Dual-Supply Operation Configuration
      2. 3.1.2 Single-Supply Operation Configuration
    2. 3.2 Common Op-Amp Configurations
      1. 3.2.1 Inverting Gain of –10 V/V
        1. 3.2.1.1 External Connections for –10 V/V Inverting Gain Configuration
        2. 3.2.1.2 Inverting Gain of –10 V/V Configuration Electrical Performance
      2. 3.2.2 Noninverting Gain of +2 V/V
        1. 3.2.2.1 External Connections to OPA593EVM for Noninverting Gain Configuration
        2. 3.2.2.2 Noninverting Gain Configuration Electrical Performance
      3. 3.2.3 Gain of +10 V/V Difference Amplifier
        1. 3.2.3.1 Jumper Shunt Locations for Difference-Amplifier Configuration
        2. 3.2.3.2 Gain of 10 V/V Difference Amplifier Configuration Electrical Performance
      4. 3.2.4 Improved Howland Current Pump
        1. 3.2.4.1 Jumper Shunt Locations for Improved Howland Current Pump Configuration
  5. 4Schematic, PCB Layout, and Bill of Materials
    1. 4.1 EVM Schematic
      1. 4.1.1 EVM Default Configuration
    2. 4.2 PCB Layout
    3. 4.3 Bill of Materials

2.5.1 Circuit Protection

The OPA593 op amp and other OPA593EVM components are protected from accidental supply reversal by the inclusion of series-connected Schottky diodes directly after the power supply jacks. These diodes exhibit a small forward-voltage drop; therefore, when setting the OPA593EVM external supply voltages, the levels must be increased slightly to accommodate the diode voltage drops. The supply voltages can be monitored at the VDD (TP17) and VSS (TP19) test points that are placed after the Schottky protection diodes. TP18 is the common for these two test points.

High-current op amps such as the OPA593 are used to drive a load that presents a complex load impedance (ZL = R±jX) at the output. If this complex impedance has significant inductive reactance, the inductance can produce a back electromotive force (EMF) voltage that could potentially damage the OPA593 output stage. The OPA593EVM has ultra-fast rectifier diodes D3 and D4 connected from the output pin to the PCB internal VDD and VSS supply lines that help provide back EMF protection. The diodes act as voltage clamps helping protect the output transistors from potential high-voltage occurrences that might occur during a back EMF event.