pslab-hardware

This repository holds PSLab Hardware design files. PSLab is a tiny pocket science lab that provides an array of equipment for doing science and engineering experiments. It can function like an oscilloscope, waveform generator, frequency counter, programmable voltage and current source and also as a data logger. The first version of hardware (V 1.0) is developed by Jithin B P, a core developer of PSLab Project.

Communication

Our chat channel is on Gitter here: https://gitter.im/fossasia/pslab

Pocket Science Lab Prototype	Front Silk Design

Content of Repository

Technical Reference Document: Latex files
Kicad Schematics, Layouts
Dimension vectors
Label vectors
Accessory development files

Platform

Microcontroller Platform : PIC24EP256GP204
IDE: MPLABX IDE v3.35 (Supported on Linux/Windows/Mac)
Compiler: MPLAB® XC16 Compiler
Programming Tool: PICkit™ 3 In-Circuit Debugger/PICkit2

KiCAD PCB front-side	KiCAD PCB back-side

Parts list

PIC24EP256GP204 - Main uC
MCP6S21 - Programmable Gain Amplifier
MCP4728 - 4 channel DAC
TC7660 - Charge Pump voltage invertor
TC1240A - Charge Pump voltage doubler
TL082 - 2 channel Op-Amp
LM324 - 4 channel Op-Amp
LM1117 - 3.3 V regulator
MCP2200 - USB-UART Bridge
or ESP8266 (ESP-12E) - UART-TCP bridge
0.5 A Fuse
100K Potentiometer
Assorted resistors, capacitors & diodes

Hardware Specs

4-Channel, up to 2MSPS Oscilloscope. Software Selectable amplification stages
12-bit Voltmeter. Programmable gain. Input ranges from +/-10 mV to +/-16 V
3x 12-bit Programmable voltage sources/ +/-3.3 V,+/-5V,0-3 V
12-bit Programmable current source. 0-3.3 mA
Supports Advanced Plugins/Add-on Modules
4-Channel, 4 MHz, Logic Analyzer
2x sine wave generators. 5 Hz to 5 KHz. Manual amplitude control for W1
4x PWM generators. 15 nS resolution. Up to 8 MHz
Capacitance Measurement. pF to uF range
I2C, SPI, UART data buses for Accel/gyros/humidity/temperature modules etc

Firmware

The firmware is available here: https://github.com/fossasia/pslab-firmware

Feature list for the acquisition and control

Oscilloscopes

One of the main features of PSLab is the 4-channel oscilloscope which can monitor analog inputs at maximum of 2 million samples per second. It includes controls such as triggering, and gain selection. Uses Python-Scipy for curve fitting.

Waveform Generators

W1 : 5 Hz – 5 KHz arbitrary waveform generator. Manual amplitude control up to +/-3 Volts
W2 : 5 Hz – 5 KHz arbitrary waveform generator. Amplitude of +/-3 Volts. Attenuable via software
PWM : There are four phase correlated PWM outputs with maximum frequency 32 MHz, 15 nano second duty cycle, and phase difference control.

Measurement Functions

Frequency counter tested up to 16 MHz.
Capacitance Measurement. pF to uF range
PSLab has several 12-bit Analog inputs (function as voltmeters) with programmable gains, and maximum ranges varying from +/-5 mV to +/-16 V.

Voltage and Current Sources

12-bit Constant Current source. Maximum current 3.3 mA (subject to load resistance).
PSLab has three 12-bit Programmable voltage sources/ +/-3.3 V,+/-5 V,0-3 V . (PV1, PV2, PV3) controls

Main Control Panel

Other useful tools

4MHz, 4-channel Logic analyzer with 15 nS resolution.Voltage and Current Sources
SPI, I2C, UART outputs
On-board 2.4 GHz transceiver for wireless data acquisition. (Work in progress..)
Graphical Interfaces for Oscilloscope, Logic Analyser, streaming data, wireless acquisition, and several experiments developed that use a common framework which drastically reduces code required to incorporate control and plotting widgets.
PSLab also has space for an ESP-12 module for WiFi access with access point / station mode.

Advanced Controls

Advanced Controls with Oscilloscope
Data Logger
Wireless Sensors (Work in progress…)
Logic Analyzer

jithinbp / pslab-hardware