Patent ID: 7271647
Filing Date: 2007-09-18
Classification: H03H

Abstract:
1. A polyphase filter comprising: a first and second cascoded differential amplifiers configured to receive a first and second differential signals, the first cascoded differential amplifier having a first resistor coupled between current legs of the first cascoded differential amplifier and the second cascoded differential amplifier having a first capacitor coupled between current legs of the second cascoded differential amplifier; and a third and fourth cascoded differential amplifiers configured to receive said first and said second differential signals, the third cascoded differential amplifier having a second resistor coupled between current legs of the third cascoded differential amplifier and the fourth cascoded differential amplifier having a second capacitor coupled between current legs of the fourth cascoded differential amplifier; wherein the first and second cascoded differential amplifiers are configured to provide a first differential output in response to the first and second differential signals and the third and fourth cascoded differential amplifiers are configured to provide a second differential output in response to the first and second differential signals.