Memo: Analog multiplier and voltage-controlled circuits

Analog multipliers are commonly available as integrated circuits (IC) and are rarely constructed from scratch due to their complexity. Multipliers commonly have 8 pinouts: X1, X2, Y1, Y2, W, Z, +VCC, -VCC. The common AD632 and MPY634 devices consist of one feedback line (W), two ground lines (X2, Y2), two supply lines (+VCC, -VCC) and one… Continue reading Memo: Analog multiplier and voltage-controlled circuits

Memo: Active frequency filters

Frequency filters attenuate signals outside its band-pass thresholds. There are two flavors of frequency filters: active and passive. Active filters have op-amps and offer amplification, as well as impedance matching functionality, of the output signal. Passive filters are simple R-C-L networks without any op-amp. Band-pass and Band-stop construction A band-pass filter is defined as follow: A band-pass… Continue reading Memo: Active frequency filters