PURPOSE: To obtain a gyrator which can obtain high Q characteristics that are indispensable for formation of a monolithic IC attained with conversion of a filter into an active RC, by connecting a capacitor between the inputs of an operational amplifier constituting an Antonion type gyrator.
CONSTITUTION: For an Antonion type gyrator, an input impedance is obtained from an equation I if the gain functions of an OP-AMP are defined as A1(S) and A2(S), respectively. Minute capacities ΔC1 and ΔC2 are added to the input terminal of the OP-AMP. Then the input impedance Zin of the equation I is shown by an equation II with addition of only the capacities ΔC1 and ΔC2. Therefore, the deterioration of Q and the deflection of L0 owing to the finite gain of the OP-AMP are limited just to C1 and C2, respectively. Then it is sufficient to decide both C1 and C2 so as to satisfy the time of compensation with C1 and C2.
KOMAZAKI TOMOKAZU
GUNJI KATSUHIKO
| JPS51100030U | 1976-08-11 |