A new monolithic variable capacitor
A method of realizing monolithic variable linear circuit elements is presented. The method exploits monolithic variable gain amplifiers to modify the values of passive integrated devices. The technique described herein realizes floating true two-terminal variable elements. A theoretical analysis of a variable capacitance cell is performed as a prelude to a practical design producing capacitances in the range of 4 pF to 30 pF. The results of theoretical analyses are compared to SPICE [1] simulations of the subject cell, prototype circuit results are presented, and performance limitations are discussed.
monolithic variable capacitor linear voltage-controlled