pslab-mini-hardware

This repository contains the PSLab-Mini hardware design files. PSLab-Mini is a scaled-down version of the PSLab board, aiming to provide instruments for doing signal measurements. It consists of an Oscilloscope, a Logic analyzer, and a Multimeter.

It also integrates an ESP chip in conjunction with the main MCU(STM32), for enabling wireless connectivity via the board.

• Firmware: https://github.com/fossasia/pslab-mini-firmware

PCB Layout

Prototype Pictures

Prototype Case

The PSLab Mini is designed to use Raspberry Pi 3/4 Cases, which are already widely available, without any modification.

All the ports remain accessible in the casing (USB, BNC Connectors, and battery connector).

Communication

• Our chat channel is on Gitter here at PSLab channel
• Our Website PSLab Website

Platform

• Main Microcontroller : STM32H563RIT6
• Secondary Microcontroller : ESP32C3
• Compiler: gcc-arm-none-eabi
• Programming Tool:
  • For uploading the bootloader onto the board: STLink/Any other ARM programmer
  • For uploading the firmware onto the board: Directly using USB (OpenBLT bootloader is already present on the board)

Parts list

• STM32H563RIT6 - Main Microcontroller
• ESP32C3 - Secondary Microcontroller(for internet connectivity)
• W25Q32JV - 32 Mega bit(4 Mega Byte) flash for ESP32
• OPA356AIDBVR - 1 channel High-Speed CMOS Op-Amp
• TLV9001IDCK - 1 channel Low-Speed CMOS Op-Amp
• IP5189T - Battery management chip
• AMS1117-3.3 - 5 V to 3.3 V buck converter
• MT2496 - 5 V to -2 V, inverting buck converter
• SP0503BAHT - ESD Protector
• Assorted resistors & capacitors

Details of the project

Design Goals

• Compact and manufacturable: All components placed on one PCB side

Core functionalities

• Oscilloscope

  • 2 channels, 12-bit ADC (at 5MSPS)
  • Uses BNC connectors to connect probes to the board
  • Higher sampling rate than the current PSLab Board

• Logic Analyser

  • 2 Channels

• Multimeter

  • AC/DC voltage, resistance, capacitance, frequency

Technical Requirements

• Interfaces
  • Open Toolchain : compiles with gcc(gcc-arm-none-eabi)
  • ADC : ≥ 2 channels, 12-bit
  • 2 x UART, 2 x SPI, 1 x I2C exposed from the chip pinout(STM32) Out of which, it has the following segregation:
    • 1 x UART, 1 x SPI - Used to interface between the ESP32 and STM32
    • 1 x UART, 1 x SPI, 1 x I2C - exposed to external headers to connect various peripherals to the board.

Pinout Used on the board.

STM32

GPIO

Instruments

BNC Connectors

Buses

ESP32

Buses

Reset functionality of the board

The reset button on the board resets both the STM32 and the ESP32 simultaneously.

In addition, the STM32 can reset ESP32 through an output pin:

PB5 (STM32) → CHIP_EN (ESP32)

Documentation related to the microcontroller

STM32

• Datasheet
• Reference manual
• HAL and LL documentation

ESP

• Datasheet
• Reference manual