The memristor discovery board is a low-cost programmable interface for exploring memristor behavior. The board plugs into the popular Digilent Analog Discovery 2 (sold separately), an affordable ‘all in one’ multi-function instrument. Download the Memristor Discovery User Manual for more information.
Memristor Discovery Open-Source Software
Software for the Memristor Discovery board is open-source and available at https://github.com/knowm/memristor-discovery. Updates are always free of charge. The Memristor Discovery app is a Java application for running memristor experiments of “applications” on the Memristor Discovery board. It is designed to be cross-platform, meaning it runs on the latest versions of MacOS, Debian-based Linux and Windows 10. Running Memristor-Discovery requires Java and the Digilent waveforms Framework to be installed on your system (see previous software link for amore details).
Analog Discovery 2 Features:
|Two-channel oscilloscope||1MΩ, ±25V, differential, 14-bit, 100Msample/sec|
|Two-channel arbitrary function generator||±5V, 14-bit, 100Msample/sec|
|16-channel digital I/O|
|2 input/output digital trigger for linking multiple instruments||3.3V CMOS|
|Two programmable power supplies||0…+5V , 0…-5V|
The Analog Discovery 2 was designed for students in typical university-based circuits and electronics class. Its features and specifications were obtained from feedback from professors at several universities and include USB control and power, small and portable form factor, robustness to withstand student abuse, and low-cost.
Analog Switch Variations
Switches are used to programmatically couple devices to the MD’s waveform generator and oscilloscopes. During enable/disable, charge accumulation due to mis-matches in PMOS/NMOS transistors can cause a voltage spike. If the spike exceeds the memristor write and erase thresholds, it will adapt (as it should). The ADG512 has higher charge injection, which can result in device writing during a selection or deselection event. If you want to perform experiments such as programmatic adding of two memristor values, please get the DG445DY variation.
|Name||Description||Blue=Cathode/Yellow=Anode, 200mV/500ns per grid tick||Blue=Cathode/Yellow=Anode, 200mV/500ns per grid tick|
|V0 ADG512||Populated with Analog Devices ADG512 analog switches (11 pC Charge Injection, 50 Ω Ron). Charge injection has been observed to cause voltage transients that exceed memristor threshold and affect memristor state during switch selection. This is not a problem for experiments on individual memristors, but can present a problem for programming multiple devices, as the act of selecting a device may disturb it’s state.||ADG512 Switch Voltage Transients on Open||ADG512 Switch Voltage Transients on Close|
|V0 DG445DY||Populated with Vishay Siliconix DG445 analog switches (-1 pC Charge Injection, 50 Ω Ron). Resolves voltage transients observed with the ADG512 switches.||DG445VY Switch Voltage Transients on Open||DG445VY Switch Voltage Transients on Close|
DIP Socket Variations
There are two 16-pin DIP socket variations, which tradeoff convenience for cost. The more expensive 3M lever DIP socket allows for risk-free connection and disconnection with the Knowm memristor chips. Use of DIP IC extraction tool (included) is recommended for less expensive press-fit DIP socket.