Page 1 of 1
thermocouple to AD in Microchip MCU
Posted: Mon Jul 24, 2023 8:56 pm
by Anthony
How can I connect a thermocouple to an AD converter in the MCU?
Can I connect it directly to the AD converter?
Re: thermocouple to AD in Microchip MCU
Posted: Tue Jul 25, 2023 4:38 pm
by Lakshmi
You cannot connect a thermocouple directly to the MCU ADC. You need to use a dedicated circuit like ADS1220 or other. Also, you need to solve the linearization of the thermocouple.
Re: thermocouple to AD in Microchip MCU
Posted: Tue Jul 25, 2023 9:53 pm
by Anthony
How to do the linearization of the thermocouple?
Re: thermocouple to AD in Microchip MCU
Posted: Wed Jul 26, 2023 6:34 am
by electrohebdo
The TC linearization depends on the IC used. In some cases the IC does the linearization, in other cases you have to do the linearization yourself via software.
Check AN1087 Analog Devices. There are other linearization techniques. For example, the arithmetic method offers high precision but requires high performance. Another method called spline has variable precision depending on polynomial degree and requires variable performance. In contrast, the linear technique has very low accuracy but requires low power. The frequently used LUT technique (Look-Up-Table) has different levels of accuracy depending on the LUT.
Check also AN844 Microchip.
Re: thermocouple to AD in Microchip MCU
Posted: Wed Jul 26, 2023 6:46 am
by rector