A low-cost gated integrator boxcar averager

Abstract

A low-cost, true integrating averager circuit has been designed for applications where low-level signal voltages must be recovered from noisy waveforms. The design separates the integrating, averaging and amplifying stages of the unit, so that correct functionality of each is guaranteed. High-quality commercially available components are combined with an optimized circuit layout, enabling the complete unit to be fabricated on one standard sized, single-sided printed circuit board, complete with on-board power supply regulation. The circuit can be incorporated into a standard housing, with a total cost of approximately ten per cent of that of a commercial unit, and the modular design means that custom modifications are easy to make. The performance of the unit is quantified in terms of the dynamic parameters of interest, and an example is given of the application to routine spectroscopic measurements. The main performance limitations are discussed in the context of the design considerations, and suggestions are made as to future improvement possibilities.