Analog-to-Digital Converter

Using a SAR Analog-to-Digital ConverterApplication Report
SBAA081 - OCTOBER 2002

Using a SAR Analog-to-Digital Converter for Current Measurement in Motor Control Applications
By Miroslav Oljaca and Justin McEldowney
ABSTRACT
With careful analysis, a designer can get good performance from what may, at first, look like incompatible components in a motor control system. One might assume that for a ±5V output signal from the current sensors, an Analog-to-Digital (A/D) converter using dual, high-voltage supplies (±12V) might be required, when in fact, new, less-expensive converters may work equally well. information. This application report will analyze the application of closed-loop current transducers and how to achieve the best signal-to-noise performance from the A/D converter. In our example, the ADS7864, a 6-channel, 12-bit,