A circuit for measuring peak potential.

The measurement of maximal potential is an integral part of several biological signal analyzers. We designed a circuit, which, unlike previously described devices that perform this function, is capable of picking a positive peak at below ground potentials or a negative peak above ground. Other features include user-selected decay characteristics, allowing beta-to-beat following and rejection of base-line noise. The circuit was implemented and tested with intracellular signals recorded from cardiac Purkinje fibers.