Patent ID: 7602210

Claim:
A two-wire transmitter for receiving power supply from an external circuit through two transmission lines and also transmitting a current signal based on a measurement value of a sensor, said two-wire transmitter comprising: a current control section to which a voltage is supplied from the external circuit, for controlling a current value of the current signal based on an electric signal responsive to the measurement value of the sensor, if current consumption of said two-wire transmitter becomes smaller than the current value of the current signal, said current control section for charging and if the current consumption becomes larger than the current value of the current signal, said current control section for discharging; a computation control section for outputting the electric signal to said current control section and also outputting a setting signal based on predetermined computation processing information; a clock supply circuit for controlling a frequency of a clock signal based on the setting signal and supplying the clock signal to said computation control section; and a constant-voltage circuit for setting output voltage of said current control section to a predetermined voltage and supplying the voltage at least to said computation control section and said clock supply circuit.