Temperature sensor using 24-bit ADC_ ADS1220
It's a prototype for an industrial temperature sensor, based on 3-wire RTD PT100, which offers the possibility to read the measurements in situ or from a remote terminal, can be used to keep the traceability of temperature storage for products.
it can operates from -30°C to 120°C temperature range, Ensure accuracy measurements +/-0.5°C.
The sensor is supplied with 2 parallel batteries to increase the capacity, which can ensure 2 Days autonomy in case of main voltage failure it contains a charging and battery protection circuit.
a P-channel MOSFET allows the power supply to switche to an external +5v DC source .
24-bit ADC from Texas Instruments is used to perform digital conversion.
Tne hardware is developed with Altium Designer.
Software Design:
The firmware is running on an stm32f103 microcontroller, based on ARM-Cortex M3 processor. and developed under Keil Uvision IDE.
Various communication protocol was implemented in this project :
- SPI protocol for ADC (bare metal)
- UART protocol for serial communication with the computer (bare metal)
- I2C for LCD (HAL librarie)
the ADC driver was developped fully with bare metal programming, which allows a direct interaction with the hardware level.
The system provides a Wi-Fi connectivity to watch the temperature measurements from a remote terminal, the firmware is still in progress.
