Abstract: An electronic chronometry system for measuring a time T between a starting instant and a stopping instant which utilizes a ramp vernier having time expansion in order to provide fine counting between a starting instant and a beginning of a clock signal and for measuring a second time between the stopping instant and a second beginning of a clock signal. The device also utilizes a rough counting device to count the number of clock periods between the beginnings of the two clock signals. The system further utilizes a compensation circuitry for determining the nonlinearity in the ramp signal in order to determine the corrective term which must be applied. The corrective term is determined during a calibration cycle as a function of the measured parameters including the first and second time periods which are measured.