Signal conditioning in industrial multi-channel data acquisition systems using Σ-Δ ADCs

introduction

In many high-end industrial applications, appropriate interface circuits need to be provided between high-performance data acquisition systems (DAS) and various sensors. If the signal interface requires multi-channel, high-precision amplitude and phase information, these industrial applications can take full advantage of the high dynamic range, simultaneous sampling, and multi-channel advantages of ADCs such as the MAX11040K . This article introduces the MAX11040K's Σ-Δ architecture and how to properly select the design architecture and external components to obtain the best system performance.

Advantages of high-speed, Σ-Δ architecture

Figure 1 shows a high-end three-phase power line monitoring/measurement system. This type of industrial application requires accurate multi-channel simultaneous data collection with up to 117dB dynamic range and 64ksps sampling rate. In order to obtain the highest system accuracy, the signals from the sensors (for example, CT, PT transformers in Figure 1) must be correctly processed to meet the requirements of the ADC input range, thereby ensuring that the performance indicators of DAS meet the requirements of relevant standards in different countries.