| 摘要 |
PROBLEM TO BE SOLVED: To provide a system for monitoring the tire pressure of a vehicle, and issuing a warning to a driver when the low tire air pressure state occurs. SOLUTION: This response-adjustable temperature sensor 306 for a transponder can measure one or a plurality of parameters and transmit a data stream to an external reader/interrogator 106. The transponder is usually operated in a passive mode wherein the electric power is acquired from an RF interrogating signal received by an antenna system, but also can be operated in a battery driving active mode. The transponder is equipped with a memory for memorizing a measured value, calibration data, a programmable trim set value, a transponder ID or the like. The temperature sensor is characterized by having a resistance, and a temperature detection circuit 306 having a temperature detection transistor Q1 for showing a predictable change of a base emitter voltage caused by the temperature and transistors P1, N1, P2, N2 connected so that a current I(T) is mirrored by the temperature detection transistor and the resistance. |
