If you build a DStat or are thinking about it, we would love to hear from you! Contact us at mdrydenatchemdotutorontodotca
Wheeler Lab DStat
Welcome to the Wheeler Lab DStat potentiostat documentation site. You can download files without logging in, but feel free to create an account if you would like to post bug reports, feature requests, or contribute (click Sign in at the top right of the page). To learn more about the Wheeler Microfluidics Laboratory, take a look at our website
The Wheeler Lab DStat is a compact open source/open hardware potentiostat designed for high performance and ease of use in the lab, specializing in sensors and other low current applications, while being inexpensive and easy to integrate into other instruments. The DStat's hardware features a powerful Atmel XMEGA microcontroller, high resolution data converters, low noise/bias current amplifiers, and a single USB connection providing both power and data. The PCB has been tailored for easy assembly—almost all components are surface mount and all large components are on the front of the board, allowing for easy reflow soldering. Voltammetric and potentiometric electrochemical experiments can be performed, and the hardware is also well suited for high quality current measurements from devices like photodiodes and photomultiplier tubes.
The DStat is controlled by a simple protocol carried using the USB Communications Device Class, which appears as a virtual serial port making direct integration with custom software easy, but for routine use, intuitive cross-platform software (written in Python) allowing instrument control and data acquisition/plotting is provided. The software supports ZeroMQ for easy communication with other programs, even across a network.
ADC: 24-bit SPI-controlled Sigma-Delta ADC with programmable input gain and digital filtering from 2.5 Hz to 30 kHz
DAC: 16-bit SPI-controlled with 35 kHz antialiasing filter
Control Amplifier/Reference Electrode buffer: 2.5 MHz bandwidth, input bias current ±200 fA
Compliance Voltage (vs. Signal Ground): ±1.46 V
WE input: input bias current ±3 fA
Maximum current output: 22 mA
Input gain settings: 100, 3k, 30k, 300k, 3M, 30M, 100M V/A
To get started, the first thing to do is to build the hardware. Take a look at the build instructions here. Once you have the hardware, see the firmware page for instructions on loading firmware onto the microcontroller. Finally, go to the interface page to get the python interface running or for details on getting the DStat to communicate with other software.
The source code and documentation of the DStat are broken into three components:
If you run into troubles, feel free to post an issue on the relevant one of the three DStat components' project pages by clicking issues in the menu at the far left. (you'll have to make an account first)
This wiki, the hardware schematics and layouts, and all other documentation describing the DStat hardware are licensed under the CERN OHL v. 1.2.
Michael D. M. Dryden 2014
You may redistribute and modify this documentation under the terms of the CERN OHL v.1.2. (http://ohwr.org/cernohl).
This documentation is distributed WITHOUT ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING OF MERCHANTABILITY, SATISFACTORY QUALITY AND FITNESS FOR A PARTICULAR PURPOSE.
Please see the CERN OHL v.1.2 for applicable conditions.
The computer interface and microcontroller firmware are free software: you can redistribute them and/or modify them under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
The computer interface and microcontroller firmware are distributed in the hope that they will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details.