The characteristic of a Tunnel Diode(TD) is approximated by the summation of two exponential terms, obtained from the haracteristic curves displayed on the curve tracer. Using this result, static characteristic of a TD pair was plotted by a computer programming. From these static characteristic curves, the triggering behavior of TC pair multi-vibrators was described graphically. Two stable characteristics were analyzed by piecewise linear Method. Theoritical switching Theoritical switching times of a TD pair flip-flop(F-F) circuits were compared with experimental results.