A switched-capacitor low-pass filter uses a capacitor switched at a clock frequency…

PHYSICS · Multi-part · Fermi University Physics · Electronics, Instrumentation & Communication · Feedback, operational amplifiers and analogue signal processing · Feedback, operational amplifiers and analogue signal processing

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Problem

A switched-capacitor low-pass filter uses a

2\,\mathrm{pF}

capacitor switched at a clock frequency

f_{\rm clk} = 500\,\mathrm{kHz}

to realise a resistor, and its passband corner is set at

f_{\rm clk}/100

. ((a)) Find the equivalent resistance

R_{\rm eq}

of the switched capacitor. ((b)) Find the passband corner frequency. ((c)) Give the band of input interference frequencies, nearest to the clock frequency itself, that will alias down into the passband.

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