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ISO7742: Some question about different stander specification

Part Number: ISO7742


We plan to use ISO7742DBQ and try to understand some spec that under different safety standers. But according some web search, unfortunately I can not get a good answer to make them clear. Thus could you please help? Details are as below:

1, Datasheet said Viotm is 3600Vpk, what is the waveform of this 3600Vpk? Is it a DC 3600V within a specified period? Or it is a pulse (eg. like sine wave) with peak voltage at 3600V?

2, Same question about Viso. The 2500Vrms is a DC waveform or AC? Or applied for both?

3, For CSA and CQC, the max working voltage is different, one is 370Vrms the other is 250Vrms. How to understand this differentiation? Why are they different? Is it because what CSA and CQC specified are different?




  • Hi Rocky,

    My responses are below:

    1. Testing is performed with a sine wave pulse with peak voltage of 3600 V. Please note that our high voltage DC performance is even better than AC performance, so if your application needs DC voltage, that's not a problem.

    2. Same answer as above. We perform testing with 2500 Vrms sine wave.

    3. CSA and CQC certificates refer to specific end-equipment standards. Those standards have other requirements and considerations such as Creepage, Clearance, CTI, Pollution Degree, Altitude, etc. One big difference between CSA and CQC tests is altitude; CSA testing assumes maximum altitude of 2000 meters and CQC testing assumes maximum altitude of 5000 meters.

    I hope this clarifies the situation.

    Saleem Marwat

    Systems Engineer

    Isolation Products, Texas Instruments