Electronic thermometer with digital read=out - has voltage to frequency converter and timer for temp. and time interval display

摘要

The miniature electronic thermometer with digital readout comprises a measuring probe (12) whose output is connected to a precision bridge driven from a stable reference source. The bridge output passes through a time-extrapolation circuit and to an integrator. The integrator operates in conjunction with a generator which produces an output of constant pulse amplitude and duration. The circuit operates as a voltage-frequency converter whose output frequency varies in sympathy with the temperature variation of the probe (14). A counter (16) comprising a decoder which counts the pulse output of the generator over a predetermined time interval, provides a digital display of the temperature. A digital logic controller allows the display to show both time intervals and measured temperature.