Digital lock in amplifier: study, design and development with a digital signal processor

摘要

In this work, the study, design and development of a Digital Lock In Amplifier (DLIA) with a Digital Signal Processor (DSP) DSP32C from AT&T is presented. To synchronize the DLIA oscillator with external signal, a Discrete Phase Locked Loop (DPLL) is added to the systems. A theoretical introduction of both systems is also presented. The algorithm of the DPLL presented is valid only for constant uniform sampling frequency.