- Projektpraktikum Elektronik
SoSe 2026 Projektpraktikum: Elektroniklabor
Prof. Dr.-Ing. Jörg Vollrath
Motivation
Ein Elektroniklabor benötigt Spannungsversorgung, Funktionsgenerator, Spannungsmesser, Oszilloskop und digitale IOs, um Schaltungen zu untersuchen und zu entwerfen.
Auf dem Markt gibt es kompakte Geräte (ADALM2000, Analog Discovery, Red Pitaya, Moku Go) die einige dieser Funktionen vereinigen.
Eine ideale preisgünstige Variante mit allen Funktionen, 4 Kanal Oszilloskop, minimaler Software Installation und schönem Userinterface ist nicht erhältlich.
Dieses Praktikum beschäftigt sich damit eine vorhandene preisgünstige Open Source Realisierung weiter voran zu treiben.
Dies ist ein Projektpraktikum mit 3 SWS begleitet von 1 SWS Projektmanagment.
Es werden Gruppen zu jeweils 4 (3) Studierenden gebildet.
Ein Block mit 180 min stehen mit Betreuung pro Woche zur Verfügung.
Am Ende wird eine Präsentation und ein Bericht bewertet.
Status
The current status of hardware and software is shown first:
Research Summary
Installation Instructions
The project is available at github JVollrath NodeEEBench.
The current version can be download as zip file NodeEEBenchV20261302.zip.
Unpack the files into "C:\temp". All files should then be in the directory "C:\temp\NodeEEBench".
The subdirectories "node" and "node_modules" contain the node executable to provide a web server and connection to a serial interface.
Hardware: BASYS3
Figure: BASYS3 FPGA Board with R2R DAC and Electronic Explorer
Hardware features:
4 channel, 12-Bit, 125 kSps, 0..1 V range ADC oscilloscope FPGA (XADC)
1 channel, 16-Bit, 30kSps, 0..3.3 V range, 15us settling time, 100k,220k R2R DAC
4k samples transfered via UART with Baud rate 230400
Pins Oscilloscope: OSC1 JXA 1 in, 7 GND; OSC2 JXA 2 in, 8 GND; OSC3 JXA 3 in, 9 GND; OSC4 JXA 4 in, 10 GND;
Pins AWG: JC upper 8 Bit 10,9,8,7,4,3,2,1; JB lower 8 Bit 10,9,8,7,4,3,2,1;
16 Bit R2R DAC: left side output D15 connected to scope 1, right side D0 and GND connection.
The FPGA configuration is done using the VHDL project files in the directory C:\temp\NodeEEBench\Xilinx\EEBench.
The Basys 3 Programming Guide guides through flash memory programming.
Hardware: Arduino
Additional ADC and DAC are realized with Digilent PMOD AD2, Digilent PMOD DA2, R2R DAC with 10k,20k resistors.
In the subdirectory Arduino are different sketches:
- "EEBench" the default configuration for NodeEEBench.bat.
- "DataConverterCharV4" realizes an R2R DAC for data converter investigation StartServerAx.bat.
Detailed description is available at Interface Electronics ADC DAC Analysis Laboratory - "DataConverterCharV5" realizes an serial C DAC for data converter investigation StartServerAx.bat.
Low cost serial DAC simulation, realization, error correction and characterization - "DataConverterCharSerialSAR" realizes a serial SAR circuit.
Software: User interface
Start the program with "C:\temp\NodeEEBench\NodeEEBench.bat".
A command window is started, the serial communication with a BASYS3 or Arduino board established and a web browser connects to "localhost:3000" to display the graphical user interface.
Besides the standard interface started with "C:\temp\NodeEEBench\NodeEEBench.bat" There is an additional special Arduino Interface for INL, DNL and SNR, FFT operation, which can be started with "C:\temp\NodeEEBench\StartServerAx.bat"
Detailed description is available at Interface Electronics ADC DAC Analysis Laboratory
Figure: Configuration and signal generator user interface
Figure: Oscilloscope and FFT interface V05
Figure: Histogram interface V06
Software features
Configuration with individual serial command transfer.
AWG: DC, stair, triangle and sine generator with frequency, amplitude and offset
OSC: 4 channel and AWG with 8..4096 sample selection, xy display, voltage and code selection, rising, falling single channel trigger, minimum, maximum, average, amplitude, period and frequency calculation.
There is voltage sample data and code data display available. A measured signal can be directly compared to the golden AWG signal in voltage or code.
FFT: AWG1, OSC1, OSC2, OSC3, OSC4 with highest magnitude frequencies and total noise magnitude for ENOB, SINAD, SFDR, SDR calculation.
Histogram with adjustable (16..256) number of bins.
Ramp Test INL, DNL
Lookup Table
Software architecture
The 3 main files are shown in the upper picture and listed here.
NodeEEBench.bat: Starting batch file
ServerEEBench.js: Javascript file for node js to create server and start communication
Projekte/NodeEEBench.html: Main user interface delivered by the nodejs server
Configuration for Arduino in folder Arduino/EEBench.
Configuration for BASYS3 FPGA in folder Xilinx/EEBench.
The folder 'Documentation' contains further information.
Unique features (Work in progress)
Signalgenerator DAC and Oscilloscope ADC integer value display.
Lookup table application for arbitrary waveform generator.
Oscilloscope data processing and feeding output to arbitrary waveform generator.
Serial interface data processing.
ADC, DAC, INL, DNL analysis.
Vorgehen 2026
- Sichten und Inbetriebnahme des vorhandenen Materials.
- Transfer auf CMOD A7
- PMOD DA2, PMOD AD2, MCP4728 DAC, I2C/SPI Digital Interface Page, SRAM Memory Buffer
- Präsentation der Ergebnisse
- Projektbericht
Planen Sie ihre Aktivitäten und überprüfen Sie ihren Projektfortschritt.
Sichern Sie Teilergebnisse durch geeignete Versionierung.
Zielsystem
Figure: Breadboard configuration of CMOD A7
Das Endergebnis ist eine Pappbox mit 2 oder 3 Breadboards.
1 oder 2 Breadboards realisieren das 4 Kanal Oszilloskop (PMOD AD2), den 2 Kanal Signalgenerator (PMOD DA2) und eine Spannungsversorgung VP+, VP-, Vref1,2 (MCP4728, TC7660S, MCP6022, R2R).
Die Eingangs- und Ausgangsspannungsbereiche werden durch Spannungsteiler und Operationsverstärkerschaltungen erweitert.
Interface und Power Dokumentation
Ein PMOD Anschluss könnte die Signal bereitstellen:
| 6 | 5 | 4 | 3 | 2 | 1 |
| VCC | GND | VP+ | AWG1 | OSC2 | OSC1 |
| VR1 | GND | VP- | AWG2 | OSC4 | OSC3 |
| 12 | 11 | 10 | 9 | 8 | 7 |
Das extra Breadboard wird die zu untersuchende Schaltung enthalten, passt in die Pappschachtel und bleibt leer.
Components:
CMOD A7 control circuit USB
PMOD DA2 AWG1,2
PMOD AD2 OSC 1,2,3,4
TC7660S negative voltage -VDD
MCP6022 rail-to-rail OpAmp
output range conversion
voltage buffer
R-voltage divider
C-buffer caps
MCP4728 VP+, VP-, Vref1,2
(USB3 PD module +10V? -> TC7600 -10V)
Projekt Ideen
- Umsetzung mit A7 CMOD FPGA
- Systematische Beschreibung von Test und Inbetriebsnahme
- Inbetriebnahme anderer Mikroprozessoren
RaspberryPi Zero, Infineon uP, TI uP, STMicro uP - Unterstützung weiterer Datenwandler: ADC, DAC
- Implementierung einer Spannungsversorgung
- Implementierung digitaler IOs und Busse (I2C, SPI, UART)
- Implementierung von Steuerung und Regelung
- Software
Test, Dokumentation, Modularisierung, Open Source, Github, Versions - Anwendungsfälle
Bauelementemessung, Datenwandler, Motorsteuerung, Ladungspumpe, Operationsverstärker, Sample and Hold, Duty Cycle Regler für Buck Converter, Schaltungen, Graphical Interface um SAR Steuerung zu implementieren - Features
Tracking, Priorisierung, Test, Hardware/Software matching - Second waveform generator AWG2
Bauteile
- A7 CMOD
- BASYS3 FPGA
- Arduino MKR WIFI 1010
- Raspberry Pi Zero W
- (Infineon, STMicro, TI MSP3240 Mikroprocessor board)
- Datenwandler PMODs: Digilent DA1, DA2, AD1, AD2; MAX
- Power supply
List?? Analog devices Eval, TI Eval board - Schaltungsbauteile
- Power ICs
Bauteile
BASYS3 Board
Arduino MKR WIFI 1010
RaspberryPi Zero W2
A7 CMOD
TI MSP3240
ST Micro Nucleo
Infineon XMC4700 Relax
PMOD ADC, DAC
Digilent
LM27762EVM
Geräte
Breadboard, Electronic Explorer, Multimeter, Seitenschneider, KomponentenabbiegevorrichtungBreadboard
Electronic Explorer
Multimeter
Seitenschneider
Abisolierer
ADALM2000
Red Pitaya
Progress 2026
11 Termine a 180 min entsprechen 3 SWS
31.03.2026 03 Projektfindungsphase
- Parallel tasks and serial tasks, task distribution
- The data converter SPI/I2C communication is the minimum requirement
- VHDL basic SPI/I2C functionality
Simulation, measurement, implementation
Configuration of interface to data converter
Optimization, synchronization of speed (baud rate), multiplexing channels - Documentation, verification and test
Merging into code
24.03.2026 02 Projektfindungsphase
- 3 Groups, 4 persons time conflict, hardware, measurement
- Hardware: 6x Arduino MKR Wifi 1010, 6x BASYS3 (CMOD A7), 6x PMODs, 6x MCP4728
- Data sheet, I2C, SPI measuremnt Arduino, Vivado Code, VHDL Code I2C, SPI
- Connecting data converters to an FPGA via SPI and I2C extending NodeEEBench project.
- Are there sufficient tasks available for 5 persons per group?
- Improvements to motivate usage of NodeEEBench
- How easy is it to start configuring BASYS 3 board.
- Document user experience challenges and satisfaction
- SPI and I2C communication with data converters
Connection, maximum speed, channel multiplexing
Measure Arduino communication signals - Make videos and/or better documentation:
System startup, attaching new hardware, FPGA/Arduino configuration, User interface change - Implement front end input/output level conversion
0 V..1 V to -5 V..5 V
17.03.2026 01 Start
- Professor and 13 students in 3 groups Tuesday 14:00-17:00
- Introduction: System block diagram with hardware and software
- Installation was done via github zip file, Arduino IDE with libraries and Vivado were installed
- Simulation and Arduino Maker WiFi 1010 was started and used with arbitrary waveform generator and oscilloscope
- Task: CMOD A7 with VHDL for SPI and I2C ADC, DAC communication was discussed
- Task: Hardware PMOD DA2, PMOD AD2, MCP4728
- Github needs short installation instructions at the main page
- Github is used at the moment as open versioned repository
Test for functionality check for check in is missing to enable pull requests in group work - Each weak at the beginning one student for each group reports status
- Each student needs a written report with contributions at the end
- There are time conflicts with other classes