This repository contains the KiCAD PCB project files for a Keithley SCAN2000 replacement card. It uses solid-state relays instead of mechanical relays.
It has a header for a flat cable connector that can be used on a breakout board, allowing the relays and input terminals to be moved to an external box, like this:
This breakout board is easier to move about than the typical huge and stiff multiconnector cable that goes into the standard board. And it already has connectors on it.
You can also use the flat cable connector for leds that indicate which input is active, but in that case you must stay below 4mA.
Apart from the above, the following changes were made to the original:
- Silk screen has been somewhat improved: added explanations of the screw terminal use.
- Programming/debugging via a standard ARM10 SWD connector is now possible. It has enough space around it for the use of a STDC14 connector. You can also still use the 2.54mm pin header.
| DMM | Tested | Works | Note |
|---|---|---|---|
| DMM6500 | ✔️ | ✔️ | |
| 2000 | ❌ | ✔️ | Not tested, but should work. The latest firmware seems to support 20 channels. |
| 2000-20 | ❌ | ✔️ | Not tested, but should work. |
| 2010 | ❌ | ❌ | Not tested, but should be the same as the Model 2002. |
| 2001 | ❌ | ❌ | Not tested, but should be the same as the Model 2002. |
| 2002 | ✔️ | ❌ | The serial clock of 2 MHz is too fast for the MCU. |
The root folder contains the KiCAD files. The bill of materials can be found in the /bom folder, while the gerber files can be found in the /gerber folder.
The design is based on the SCAN2000 pcb made by George Christidis. It also uses an STM32G0, but the pcb design is done in KiCAD 7 and corrects several problems like incorrect dimensions of the original design and replaces hard to obtain parts like the resistor arrays. The card was tested in a Keithley DMM6500 (successfully) and a Keithley Model 2002 (not successfully).
The source code and installation instructions can be found here. You will need a ST-Link adapter to flash the MCU. The source code published on the original repo has serious flaws (at the time of my publishing).
There is no need for external repositories, all non-default symbols, footprints and 3d models are included in this repository.
This work is released under the Cern OHL v.1.2 - see www.ohwr.org/licenses/cern-ohl/v1.2 or the included LICENSE file for more information.