| 摘要 |
PURPOSE:To make the high accuracy mesurement over a long period of time possible without using amplifiers of small drift by opening a switch connected in series between a signal source and an amplifer and at the same time, by closing a swtich between the signal ground and an amplifer thereby outputting the correction value for the measured value. CONSTITUTION:If a switch 2 connected in series between a signal source 8 and an amplifier 4 is opened and a short circuiting switch 3 between an amplifier 5 and the signal ground is closed prior to performing measurement of an analog signal source 8, a drift output is generated from the amplifier 4, and is supplied via an A/D converter 5 to a microcomputer 6. The switches 2, 3 are closed and opened, respectively and are used for correction of the mesured value during signal measurement. With such simple constitution, the microsignals are measured with high accuracy without any drift, etc. over a long time without using any amplifiers of small drift. |
