Thermal management in a pressure transmitter

A miniaturized pressure transmitter, comprising:

• a transmitter housing with an outer wall providing thermal resistance, the outer wall separating an isothermal island formed in a first end of the housing from a heat sink island formed in a second end of the housing;
• the isothermal island including a fluid inlet, a pressure sensor configured to receive a pressure from the fluid inlet and a temperature sensor;
• the heat sink island including an electrical connector with an outer shell and a feedthrough with contacts, and a primary heat load device that is thermally coupled to the outer shell, the contacts configured to connect the transmitter to an external current loop circuit and to carry a current controlled by the transmitter, and a portion of the current being conducted by the primary heat load device;
• and
• a circuit board electrically coupled to the pressure and temperature sensors and to the primary heat load device, the circuit board configured to control the current to provide a temperature-compensated, high accuracy representation of pressure.

A miniaturized pressure transmitter, comprising:

• an outer housing having a fluid inlet at a first end, an electrical feedthrough with contacts and an outer connector shell at a second end, the contacts configured to couple the transmitter to an external current loop, and an integral outer wall extending between the inlet and the connector shell, the housing having a central axis extending from the first end to the second end;
• a transducer disposed in the housing having a pressure sensor fluidly coupled to the inlet and a temperature sensor, the pressure sensor being in thermal contact with the fluid inlet and the temperature sensor;
• a circuit board electrically coupled to the transducer and having a controlled current output that is coupled to the contacts and that represents the pressure, the circuit board being arranged transverse to the central axis;
• and
• a transistor that conducts a portion of the controlled current and that is thermally coupled to the connector shell, the integral wall having a length sufficient to thermally decouple the transducer from the transistor.