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Registered: ‎12-03-2014

Measuring the CMTI Performance of the Si87xx CMOS Optocoupler Replacements

[ Edited ]


This video demonstrates the Si87xx digital isolator transient immunity using a well-regarded, calibrated, commercial CMTI tester so you can see exactly how we measure CMTI performance of our products. The side-by-side comparison of the common mode transient immunity (CMTI) clearly displays the robustness of the Silicon Labs digital isolator optocoupler replacement devices vs. standard optocoupler devices.


CMTI is the ability of an isolation device to maintain data integrity during fast common mode transient events. Common mode transients can result from a number of sources such as IGBT drive circuits, fast high-voltage or high current switching loads, motor drives and floating power supplies. Local parasitic paths on the isolator or circuit board can couple across the isolation barrier, causing data errors that compromise system integrity. The Silicon Labs Si87xx series offers 2 to 3 times lower parasitic capacitance compared to even the most advanced optocouplers available. This reduced coupling translates into higher CMTI for improved system reliability and performance; especially important in high availability applications such as power delivery and communication systems.


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