SBAA783 January   2026 ISOM8600 , ISOM8610

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Digital Output in PLC/DCS, Motor Drives and Robotics
    1. 1.1 Sink and Source Outputs: Supports Bidirectional Operation
    2. 1.2 PLC/DCS
    3. 1.3 Motor Drives
    4. 1.4 Robotics
  5. 2Design Procedures for Driving a Relay (Inductive Load)
    1. 2.1 Introduction to a Mechanical Relay
    2. 2.2 ISOM8600 Design Example
    3. 2.3 Test Results based on ISOM8600 and relay
      1. 2.3.1 Test 1: No Protection
      2. 2.3.2 Test 2: Capacitive Filter
      3. 2.3.3 Test 3: Zener Active Clamping Diode
  6. 3ISOM86x0 Advantages
    1. 3.1 Isolation Technology
    2. 3.2 Opto-Emulator Signal Chain
  7. 4Summary
  8. 5References

3.1 Isolation Technology

ISOM86x0 implements TI's latest opto-emulator technology which uses TI's patented SiO2 insolation material as a dielectric. SiO2 offers the highest dielectric strength in industry unlike airgap or epoxy based isolation utilized in opto-couplers.

Table 3-1 Dielectric Strength of Various Insulating Materials
Insulator Materials Technology Dielectric Strength
Air Optocouplers approximately 1VRMS/µm
Epoxies Optocouplers approximately 20VRMS/µm
Silica Filled Mold Compounds Optocouplers approximately 100VRMS/µm
SiO2 Opto-emulators and Digital Isolators approximately 500VRMS/µm

LED signal transmissions in opto-couplers are affected by aging, therefore upgrading to the ISOM8610 also offers another benefit. TI's optocoupler does not use and LED. Instead, the diode characteristics are emulated. This means that the opto-emulators can certify according to the more stringent standard IEC 60747-17 with lifetime isolation testing. The standard for traditional optocouplers - IEC 60747-5-5 - does not require lifetime testing of the isolation barrier. Therefore, opto-emulators can provide better device performance and capability over lifetime (Demystifying Isolation Certification Standards: Optocouplers vs Opto-emulators).

Optocoupler Cross-Section Figure 3-1 Optocoupler Cross-Section
Opto-Emulator Cross-Section Figure 3-2 Opto-Emulator Cross-Section

Additionally, the ISOM86x0 opto-emulator switch offers advantages like wider temperature ranges and tight process controls resulting in small part-to-part variations. Since there is no aging effect to compensate for, the emulated diode-input stage consumes less power and enables system power saving than optocouplers that have LED aging and require higher bias currents over the device lifetime.