Question about LTC2360

Question

Hello, 
 I have a question about the following description written in the LTC2360 data sheet page 18. 
 Regarding the description &ldquo; using three-state buffers to isolate the ADC data bus &rdquo; , which of the signals, SDO, CONV and SCK, needs an external three-state buffer? 
 I think all of them don &rsquo; t need a three state buffer since SDO is Hi-Z during conversion and CONV and SCK are input. 
 Is my understanding of that incorrect? 
 
 Regards, 
 Kazu

ghoover · Answer

Using a three state buffer is not required but if the bus has activity from other devices during the time a conversion is happening using the three state buffers can reduce errors caused by capacitive coupling. The capacitive coupling can occur even if the SDO output is in Hi-Z mode. The easier alternative is to suspend any activity on the bus during a conversion.