| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve size reduction by pin saving by processing an analog signal and a digital signal through the same A/D port of an IC having A/D conversion processing such as a microcomputer. <P>SOLUTION: A temperature determination system 10 includes a determination part 20, a temperature detection part 30, a priority signal generation part 40, and a level shift part 50. An A/D port 22 of the determination part 20 acquires output of the temperature detection part 30. The temperature detection part 30 includes a thermistor Rth, a level adjusting resistance Rc, and a voltage dividing adjustment resistance Rx. The priority signal generation part 40 is a general digital signal generation circuit, and outputs an ON signal to the level shift part 50 as a priority signal generation switch SW11 turns on with a predetermined control signal. A transistor Tr1 of the level shift part 50 turns ON with the ON signal output from the priority signal generation part 40 to shift the signal level of the A/D port 22 to a ground level. <P>COPYRIGHT: (C)2012,JPO&INPIT |
