Measurement of Bandpass Sigma-Delta Modulator Coding Efficiency and Pulse Transition Frequency for RF Class D Power Amplifier Applications

Measurements of the coding efficiency and average transition frequency of a bandpass ΣΔ modulator pulse train are shown. The parameters are important in RF class D amplifier applications and affect the power efficiency of the amplifier. A fourth order bandpass ΣΔ modulator implemented in a SiGe process is used for experimentation and compared with simulated results.

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