| 摘要 |
PURPOSE:To make one chip implementation possible and obtain necessary accuracy by changing over the switch of resistance RADA circuit by the output obtained by comparing the output caused by the diode temperature sensor with that of the resistance RADA circuit. CONSTITUTION:The constant voltage circuit 13 is connected in parallel with the power source 14. The standard voltage Vref is formed by supplying the output of the circuit 13 to the RADA circuit 15. Moreover, the constant voltage and constant current dispersion simultaneous compensation circuit 16 is connected between the constant current circuit 17 and constant voltage circuit 13. Further, the output of the circuit 15 and voltage VD by the diode temperature sensor 11 driven at the constant current, are differentially amplified by the differential amplifier 12. Moreover, the switch 18 of the circuit 15 is changed over by the output Vo of the amplifier 12 and voltage of + side input terminal of the amplifier 12 is varied. After that, switching action of the switch 18 is stopped by turning the output Vo reversely and the temperature is detected as the digital value. The realiability is high because said constructed circuit is formed on the substrate of one chip. Also, its accuracy can be made according to use. |
