| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an analog input signal processing circuit capable of individually adjusting an input filter characteristic and an input gain. <P>SOLUTION: Signal voltages generated by variable analog signal sources 100a, 100b are input to a mricroprocessor 110 via gain adjustment circuits 10a, 10b, switched capacitor filter circuits 20a, 20b, and analog comparison circuits 30a, 30b, respectively. The mricroprocessor 110 in cooperation with a program memory 111 generates control signal pulse trains CNTa, CNTb with a variable period and a variable duty, and the filter characteristic is adjusted depending on the period of the control signal pulse trains CNTa, CNTb and the gain is adjusted by the pulse duty. Even when comparison reference voltages 31a, 31b of the analog comparison circuits 30a, 30b are fixed values, the comparison reference voltages can apparently be revised and adjusted by adjusting the gains of the gain adjustment circuits 10a, 10b. <P>COPYRIGHT: (C)2007,JPO&INPIT |
