Other Parts Discussed in Thread: TIDA-00555, , AMC1100, AMC3330
Hello ,
I have been studying the voltage measurement techniques using AMC1100 and AMC1200 as in TIDA-00555.
I have two questions regarding the design.
First , what is the function of the negative rail (-5V_WSH) that has been generated using negative LDO ,
The AMC1200/1100 is powered from single isolated 5V and GND. I can see that the diodes at the amplifier inputs are connected to the negative rail but that could be replaced by GND instead.
My second question is regarding keeping the common mode voltage within the acceptable range of the amplifier (Maximum 5V) I will be measuring high AC voltages up to +/-250VAC
Under this condition is connecting the "GND_PH" of the amplifier to the neutral enough for keeping the VCM within limits or should I go with a configuration like shown in figure below ?
I have also seen a configuration like the one shown in the previous image but it uses 2 AMC1200/1100 instead of one
I don't really understand the difference between these configurations and which one is suitable for my application?
Thank you very much in advance.
BR
Amr
