| 摘要 |
PURPOSE:To detect a microsignal highly accurately by finding the difference between an offset component superposed by the microsignal and the 1st reference signal and then finding the difference between said differential output and the 2nd reference signal. CONSTITUTION:The 1st differential circuit 2a finds the difference once and the 2nd differential circuit 2b finds the difference again between the 1st differential output and an offset component of which gain is properly adjusted by a gain adjuster 1. The titled circuit is also provided with a fixed impedance 3a and a variable impedance 3b. Rectifying diodes D1, D2 can be omitted when the offset component vc is DC. In this example, differential amplifiers 4a, 4b are used in the differential circuits 2a, 2b. |
