DSO

Multi-Channel Digital Storage Oscilloscope (DSO)

A custom Multi-Channel Digital Storage Oscilloscope (DSO) designed using the STM32F103C8T6 microcontroller. This project combines a custom analog front-end, trigger circuitry, anti-alias filtering, multi-channel acquisition architecture, and a TFT display into a compact oscilloscope platform.

The analog signal conditioning was designed and verified in LTspice, while the complete hardware was developed in KiCad, including schematic capture, PCB layout, and 3D visualization.

Features

• Multi-channel analog acquisition architecture
• Custom analog front-end
• Input over-voltage protection
• Adjustable gain stage
• DC offset stage
• Hardware trigger comparator
• RC anti-alias filter
• STM32F103 ADC interface
• TFT display interface
• SWD programming and debugging
• Two-layer PCB
• LTspice verified analog stages

Hardware Specifications

Repository Structure

Multi-Channel-DSO/
│
├── BOM/
│   └── DSO.xlsx
│
├── images/
│   ├── KiCad/
│   │   ├── PCB.png
│   │   ├── PCB_3D.png
│   │   ├── PCB_3D_through.png
│   │   ├── Schematic.png
│   ├── LTspice/
│   │   ├── Final_output.png
│   │   ├── Input_waveform.png
│   │   ├── Gain_waveform.png
│   │   ├── offset_waveform.png
│   │   └── Spice_Schematic.png
│
├── KiCad/
│   ├── DSO.kicad_pro
│   ├── DSO.kicad_sch
│   └── DSO.kicad_pcb
│
├── LTspice/

System Architecture

                Analog Input
                     │
                     ▼
             Input Protection
          (TVS + Clamp Diodes)
                     │
                     ▼
             Buffer Amplifier
                     │
                     ▼
           Programmable Gain Stage
                     │
                     ▼
              DC Offset Stage
                     │
                     ▼
           Trigger Comparator
                     │
                     ├────────► STM32 Trigger Input
                     │
                     ▼
            RC Anti-Alias Filter
                     │
                     ▼

Analog Signal Chain

The complete analog front-end consists of:

• Input protection
• Voltage scaling
• Buffer amplifier
• Gain amplifier
• DC offset stage
• Trigger comparator
• RC anti-alias filter
• ADC interface

The design conditions incoming analog signals into the STM32 ADC input range while maintaining waveform integrity.

LTspice Simulation

The complete analog signal chain was verified before PCB implementation.

Simulation stages include:

• Input waveform
• Gain stage response
• Offset stage response
• Final conditioned output
• Complete analog schematic

PCB Design

The PCB was designed using KiCad with emphasis on:

• Compact component placement
• Analog and digital section separation
• Ground plane implementation
• Short analog signal routing
• Decoupling capacitor placement
• SWD programming interface
• TFT display interface

Development Workflow

• Analog front-end design
• LTspice verification
• Schematic capture
• PCB layout
• 3D PCB visualization
• BOM generation
• Embedded firmware development (in progress)
• Hardware validation (planned)

Software Used

• KiCad 9
• LTspice
• Git
• GitHub

Future Improvements

• Dual simultaneous ADC acquisition
• External high-speed ADC
• DMA circular buffer implementation
• Auto trigger mode
• Single-shot trigger
• FFT spectrum analyzer
• USB waveform streaming
• SD card waveform storage
• Automatic measurements
• Cursor functions
• Frequency and duty-cycle measurement
• Rotary encoder user interface

Author

Aryan Kodan

Electronics Engineering | Embedded Systems | PCB Design | Analog Circuit Design | VLSI

GitHub: https://github.com/Aryan-Kodan

License

This project is released under the MIT License.