AMC1350-Q1: AMC1350 output RC filter and stability

Hi Frederic,

I'm not seeing what you are referring to where the 'spec says that if R=0 the max. "OUTP to OUTN" cap is 250pF'.  We do have a max capacitive load of 250pF between OUTp and OUTn shown in section 6.3 (page 4, AMC1350-Q1 datasheet).  This is just a limitation of the device's ability to drive a capacitive load.  Once there are series resistors in place, your 100 ohm for example, you should be able to have capacitor values well into the 100s of nano farad range.  The limitations would fall on the rest of the signal chain after the isolation amplifier more so than the AMC1350 itself.  What are you driving downstream from the AMC1350?

Hello Tom,

About" Once there are series resistors in place, your 100 ohm for example, you should be able to have capacitor values well into the 100s of nano farad range."

How can I be sure that for example R=100ohm + C=100nF will not be an issue (stability) for AMC1350?

Thanks,

Frederic

Hello Tom,

Thanks. I wasn't sure the spice model was good enough to check the stability with a capacitive load.

I will simulate this using pspice.

Most amplifiers have a chart for "capacitive load stability" that provides R vs C limits. It would be nice to include this in spec in the future.

Thanks,

Frederic

Thank you for the comment, we'll consider adding a similar table.