Hi, I am mainly worried about damage to the chip. I can guarantee that all my differential input voltages will be below 2Vpp, as listed in the spec sheet under maximum input voltage swing page 5. However, because I am using 0.1uF capacitor and the internal analog high-pass filter, signal around ~50kHz is amplified by 10db as shown in figure 19. So there is a ~2Vpp*3=6Vpp signal around 50kHz. I think the spec to look would be the absolute maximum rating between analog input pins and AVSS (ground) listed as 3.6V in the spec sheet page 4. So 6Vpp would be 3V between input pin and ground due to AC coupling. 3V is below the absolute maximum rating. However, for the National Instruments digitizer NI-5752, which uses AFE5801 with 1uF external AC coupling I found the gain around 50kHz to be higher than noted in the AFE5801 specsheet ~16db, at least for 60 mV input swings. For 16db the voltage swing at 50kHz would be ~2Vpp*6=12Vpp, which corresponds to a 6V between input pins and ground. However I am not sure if these max ratings for the input pins really apply to this internal gain around 50kHz. In my understanding since the DHPF is digital, the filter only acts after the signal is digitized and the ADC would still see the gain at 50kHz. Jens
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