MULTI-STAGE SWITCHED-CAPACITOR DC BLOCKING CIRCUIT FOR AUDIO FRONTEND

摘要

An integrated DC blocking amplifier circuit, including: an operational amplifier configured in a differential amplifier; and at least first and second two-stage switched-capacitor circuits, each two stage switched-capacitor circuit including a first-stage circuit and a second-stage circuit, wherein the first two-stage switched capacitor circuit is connected to a positive feedback path of the operational amplifier and the second two-stage switched capacitor circuit is connected to a negative feedback path of the operational amplifier, wherein the first-stage circuit is switched at a relatively low switching frequency, while the second-stage circuit is switched at a relatively high switching frequency.

主权项

1. An integrated DC blocking amplifier circuit, comprising:
an operational amplifier configured in a differential amplifier mode and having at least a positive input and a negative input; and at least first and second two-stage switched-capacitor circuits, each two stage switched-capacitor circuit including a first-stage circuit and a second-stage circuit,
wherein the first two-stage switched capacitor circuit is connected to a positive feedback path of the operational amplifier and the second two-stage switched capacitor circuit is connected to a negative feedback path of the operational amplifier,wherein the first-stage circuit of the at least first and second two-stage switched-capacitor circuit is switched at a relatively low switching frequency, while the second-stage circuit of the at least first and second two-stage switched-capacitor circuit is switched at a relatively high switching frequency.