That may or may not be PSpice specific. I thought about it some. Start with a "standard" track and hold, add a fast comparator to convert to a peak and hold (two if you want both peaks). Add some enable circuitry to handle any ADC converter setup and hold times and data transfer as needed.. Did something like this about 20 years ago for what was then Hughes EDSG. Location of the analog / digital boundary is engineer choice.