Part Number: AMC1350
I am using an AMC1350 for AC Mains monitoring and have found that it draws a slug of current on VDD2 at the negative zero crossing of the input waveform at INP, with INN tied to GND1.
Is this to be expected? There are 1uF decoupling caps from both VDD1-to-GND1 and VDD2-to-GND2 right next to the package. This slug causes enough disturbance to the VDD2 supply to affect other circuits using the same 5V supply.
This seems unusual and I'd like to know if this should be expected, and how much variability can be expected?
Screenshots are attached and they were acquired on a prototype board. I inserted 10 ohms between the GND connection of my proto board and the bench supply. I referenced all the scope connections to the board GND connection and inverted the I_5VA measurement on Channel 4 to represent the current into the 5VA connection. The ACV waveform on Channel 1 is from a diff-amp measuring OUTN-OUTP with a ~2.5V offset.
Thank you for your help!
Jeff
