asrock70
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I need to heat and measure the temperature of several components within one device.
Measured temperature up to 90C, required resolution 0.1C, required size so that even with the supply cable it fits into the cable eye,cable length up to 50 cm. A relatively cheap and robust solution allowing the measurement of at least 4 temperatures, evaluable with something like the STM32F303 I normally use thermocouples or DS18B20.
the state of the semiconductor market makes evaluation ICs for thermocouples expensive and the DS18B20 is too big in TO-92.
For a while, I was thinking about an NTC thermistor, as I am mainly concerned with temperatures above 60C and there the thermistor's characteristics are quite unsuitable. I don't think it's appropriate.
Another idea is the TC1047A. The SOT23 case with SMD 100nF and the three-wire supply cable fits into the cable eye, it is not a problem to cover it with epoxy. Output is 10mV/C 1.5V for 100C, If use internal PGA in MCU x2 have for 3,3V Vref max mesured teperture 115C and output 20mV/C if LSB of ADC is 0,8mV ,that's resolution 0,04C, 0,08 without PGA.
So much theory, how practical, what the lead wire will do, etc. Alternatively, what do you use as temperature sensors in similar cases?
Measured temperature up to 90C, required resolution 0.1C, required size so that even with the supply cable it fits into the cable eye,cable length up to 50 cm. A relatively cheap and robust solution allowing the measurement of at least 4 temperatures, evaluable with something like the STM32F303 I normally use thermocouples or DS18B20.
the state of the semiconductor market makes evaluation ICs for thermocouples expensive and the DS18B20 is too big in TO-92.
For a while, I was thinking about an NTC thermistor, as I am mainly concerned with temperatures above 60C and there the thermistor's characteristics are quite unsuitable. I don't think it's appropriate.
Another idea is the TC1047A. The SOT23 case with SMD 100nF and the three-wire supply cable fits into the cable eye, it is not a problem to cover it with epoxy. Output is 10mV/C 1.5V for 100C, If use internal PGA in MCU x2 have for 3,3V Vref max mesured teperture 115C and output 20mV/C if LSB of ADC is 0,8mV ,that's resolution 0,04C, 0,08 without PGA.
So much theory, how practical, what the lead wire will do, etc. Alternatively, what do you use as temperature sensors in similar cases?