A pseudo-random sampled circuit and its applications.

摘要

This dissertation presents an unconventional approach to sampling circuits. A pseudo-random sampling design method is developed and applied to realize a large on-chip resistance-capacitance (RC) product circuit, despite the use of a small, and therefore integrable, capacitor.;The challenge of designing a large RC product with small capacitance is to create a very large resistance. A new method of realizing a very large resistance using a pseudo-random sampling switch with a small capacitor or a small resistor is developed, designed, and tested in a discrete and an integrated circuit form. The large resistance is applied to design a very high, but finite, input impedance amplifier, simple RC filters with very low cut-off frequencies, and AC coupling between on-chip amplifiers without requiring external capacitors.;The new circuit design technique to create large resistance requires small chip area, thereby implying low cost and potentially high yield. An advantage of small chip area is less parasitic capacitance. Other advantages of the new circuit design method are the preservation of on-chip matching accuracy by integrating all components and user programmable features through the use of on-chip switches. The important attribute of the circuit is that it maintains the advantages of uniform sampled circuits, such as the switched-capacitor filter/ amplifier, while overcoming the frequency limitation of these uniform sampled circuits.