Fully open source nV level measuring instrument (super awesome, including PCB, schematic diagram, firmware, etc.)

This awesome project comes from the nV-level measurement instrument challenge launched by xDevs. The project requirements are relatively difficult and only one author has completed it. The author has open sourced all project materials and provided detailed explanations (in English).

Schematic PCB

BioAmp EXG Pill: Professional small, powerful analog front end (AFE) biopotential signal acquisition board (schematic, PCB, software, etc.)

The BioAmp EXG Pill is a powerful small analog front end (AFE) biopotential signal acquisition board that pairs with any microcontroller unit (MCU) or single board computer (SBC) with an analog-to-digital converter (ADC)) Such as Arduino UNO & Nano, Espressif ESP32, Adafruit QtPy, STM32 Blue Pill, BeagleBone Black and Raspberry Pi Pico, just to name a few. It also works with any dedicated ADC such as Texas Instruments ADS1115 and ADS131M0x etc.

Schematic PCB

CN0079

High-precision digital-to-analog conversion using AD5542/AD5541 16-bit voltage output DACs, ADR421 voltage reference, and AD8628 auto-zero op amp

CN0200

18-Bit, Linear, Low-Noise, Precision Bipolar ±10 V DC Voltage Source

Schematic PCB

CN0203

Flexible PLC/DCS analog output module using only two analog devices

Schematic PCB

CN0202

Flexible, high-precision, low-drift PLC/DCS analog output module

Schematic PCB

CN0204

Flexible, high-precision, low-drift PLC/DCS analog output module

Schematic PCB

CN0257

20-Bit, Linear, Low Noise, Precision, Unipolar +10 V DC Voltage Source

Schematic PCB

CN0182

Single-supply, low-power programmable window detector

Schematic PCB

CN0183

Precision, 16-bit bipolar output voltage source using +12V to ±5V supplies

Schematic PCB

CN0229

4-channel, flexible, configurable, voltage and current output circuit for I/O card and PLC applications

Schematic PCB

CN0267

Complete 4 mA to 20 mA loop powered field instrument with HART interface

Schematic PCB

CN0270

Complete 4 mA to 20 mA HART solution

Schematic PCB

CN0278

Complete 4 mA to 20 mA HART solution with additional voltage output capability

Schematic PCB

CN0318

16-Bit, Linear, Ultra-Stable, Low-Noise, Bipolar, ±10 V DC Voltage Source

Schematic PCB

CN0321

Fully isolated, single-channel voltage, 4 mA to 20 mA output with HART

Schematic PCB

CN0348

16-bit, single-supply, buffered voltage output analog-to-digital converter with less than ±1 LSB integral and differential nonlinearity

Schematic PCB

CN0191

20-bit, linear, low-noise, precision, bipolar ±10V DC voltage source

Schematic PCB

CN0179

4-20 mA Low Power, 14-Bit, Process Control Current Loop Transmitter

Schematic PCB

CN0177

18-Bit, Linear, Low-Noise, Precision Bipolar ±10 V DC Voltage Source

Schematic PCB