Question about ADM2486 fail-safe

Question

Hello, 
 I have some questions about the fail-safe function of the ADM2486. 
 How is the fail-safe realized in spite of the specification of &plusmn;200mV differential input threshold voltage? 
 Also, is it necessary to add any external circuit for fail-safe when the A and B inputs are shorted? 
 Best Regards, 
 Kazu

ericb · Accepted Answer

The ADM2486s fail-safe feature works by providing a small bias to the A & B pins which will keep Va-Vb >200mV when the A & B pins are open circuited. 
 If the A & B pins are shorted together, then the receiver input voltage will presumably be within the +/-200mV and the output will be indeterminant. 
 If you need fail-safe operation under a shorted bus condition, then I'd suggest using one of our other parts with an asymmetric threshold voltage, such as the MAX14938/9 
 Eric)

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Question about ADM2486 fail-safe