AlGeorge
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Hi all. I am designing a PIC or AVR with temperature sensor: eg Linear Active Thermistor LM35 and Microchip mcp9700. Unfortunately, they do not have the resolution I need:
Range 33c-40c (less than 7degC range)
Accuracy better than .01C
Response seconds
Distance skin contact, or intimate to skin
Both chips above only do 10mv/1c. Sure they can be boosted by another analog device, but specs demand minimal parts.
The 8-bit PIC comparator is likely not as suitable as the 10-bit AVR device.
I have never designed temperature sensors, and all designs seem to cater for wider temperature ranges.
Which leads me to the main question - given the above parameters, is there an IR receiver that does not need a sender, with better resolution than aforementioned?
From what Ive been able to ascertain Thermistors provide the best accuracy. Some items here may be suitable.
https://www.amwei.com/news.asp?news_id=79
These devices are providing a 1k2 swing in the 35-40degC range/240?/deg/>1% accuracy.
However, I am still most interested in Infrared, as the desired temperature is underneath the skin.
Any suggestions please?
Alistair George
Range 33c-40c (less than 7degC range)
Accuracy better than .01C
Response seconds
Distance skin contact, or intimate to skin
Both chips above only do 10mv/1c. Sure they can be boosted by another analog device, but specs demand minimal parts.
The 8-bit PIC comparator is likely not as suitable as the 10-bit AVR device.
I have never designed temperature sensors, and all designs seem to cater for wider temperature ranges.
Which leads me to the main question - given the above parameters, is there an IR receiver that does not need a sender, with better resolution than aforementioned?
From what Ive been able to ascertain Thermistors provide the best accuracy. Some items here may be suitable.
https://www.amwei.com/news.asp?news_id=79
These devices are providing a 1k2 swing in the 35-40degC range/240?/deg/>1% accuracy.
However, I am still most interested in Infrared, as the desired temperature is underneath the skin.
Any suggestions please?
Alistair George