The purpose of this precision design is to design an optimal, high-voltage, multiplexed, data-acquisition system for highest system linearity and fast settling. The overall system block diagram is illustrated in Figure 43. The circuit is a multichannel, data-acquisition signal chain consisting of an input low-pass filter, mux, mux output buffer, attenuating SAR ADC driver, and the reference driver. The architecture allows fast sampling of multiple channels using a single ADC, providing a low-cost solution. This design systematically approaches each analog circuit block to achieve a 16-bit settling for a full-scale input stage voltage and linearity for a 10-kHz sinusoidal input signal at each input channel.
||For step-by-step design procedure, circuit schematics, bill of materials, PCB files, simulation results, and test results, refer to TI Precision Design TIPD151, 16-Bit, 400-kSPS, 4-Channel Multiplexed Data-Acquisition System for High-Voltage Inputs with Lowest Distortion.|