Design of single-supply ADC system for industrial signal level

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Single chip microcomputer STM32L151CCU6

1206RGB (single)

Industrial Router Crystal 3.2*2.5mm 3225 26M (26.000MHZ) 12PF 10PPM 20PPM 30PPM

The outer diameter of the probe domestic P156-G flat nickel plated needle is 2.36mm.

Overview:
Connection/reference device
AD7176-2 24-bit, 250 kSPS Σ-Δ ADC with setup time 20 μs
AD8475 Precision, Selectable Gain, Fully Differential Funnel Amplifier
ADR445 5 V Ultra Low Noise LDO XFET Voltage Reference Evaluation and Design Support Circuit Evaluation Board
AD7176-2 Circuit Evaluation Board (EVAL-AD7176-2SDZ)
System Demonstration Platform (EVAL-SDP-CB1Z)
Design and integrate file schematics, layout files, bill of materials

Circuit Capabilities and Benefits When sampling industrial level signals, you must provide fast, high-resolution conversion information. Typically, analog-to-digital converters (ADCs) have a maximum resolution of 14 bits to 18 bits when the sampling rate reaches 500 kSPS. The circuit shown in Figure 1 is a single-supply system optimized for industrial-level signal sampling, integrating a 24-bit, 250 kSPS Σ-Δ ADC. Each of the two differential channels or four pseudo differential channels can It is scanned at 17.2 bits of noise-free code resolution at a rate of up to 50 kSPS.
This circuit uses an innovative differential amplifier with built-in laser trimming resistors to perform attenuation and level shifting, and a precision ADC with low supply voltage can be used to achieve standard industrial-level signals of ±5 V, ±10 V, and 0 V to 10 V. The problem of digitizing. Applications for this circuit include process control (PLC/DCS modules), medical and scientific multichannel instruments and chromatographs.

Figure 1. High-precision, 24-bit ADC driver for industrial signals (schematic diagram: all connections and decoupling not shown)
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