This is regarding the RS422 bus hardware. I have a receiver that has Vih of 1.8V and a max of Vcc(3.3V).
Supposing I link a driver and receiver up. The driver,as per the EIA RS422 standards state that it can supply +/-6V differential. But since its dc levels I am reckoning it will be in the range of 6V and 0V.
Now, the receiver has a Vih of min 1.8 to 3.3V. I have posted this before but somehow I am not able to understand how I can directly interface them without a voltage divider. But using a voltage divider has its issues of impedance loading. I understand RS422 has a charachteristic impedance of 100Ohms. Now, I am just analysing the effect of passives on the charachteristic impedance on the addition of extra passives. So, supposing, I add some resistors as shown, what will the impact be ?
Also, I have a requirement that states that Differential input voltage Vdi - 600mV < Vdi < 6V(each voltage inside this range is interpreted as a signal). But, I selected a receiver as stated -
Will this work out ?
I just looked at this RS422 receiver - RS422 receiver. The Vid = -12V to +12V. What is the reason for such different Vids in the same standard ?