Connecting LM335Z temperature sensors to the P2
Tubular
Posts: 4,705
These LM335Z temperature sensors are sometimes described as 'venerable' but they have the advantage of being relatively available
This code takes advantage of the 1mA pull-up current source built into every P2 smart pin, to power/bias the LM335Z sensor, which connects between the P2 I/O Pin and ground. No other components are necessary, unless you want to trim the zero (using a 10k trimpot). This is MicroPython code, but easy translates to other languages
In the plot window I've used finger pressure to heat the LM335Z, and a really short burst of cooling spray to go below the zero, then finger pressure to heat up again.
I'll post the LM334Z code soon, too. The LM334Z is nicer in that you can trim for 1.65v zero point, so you can use the 'zoom' ADC ranges of the P2
This code takes advantage of the 1mA pull-up current source built into every P2 smart pin, to power/bias the LM335Z sensor, which connects between the P2 I/O Pin and ground. No other components are necessary, unless you want to trim the zero (using a 10k trimpot). This is MicroPython code, but easy translates to other languages
In the plot window I've used finger pressure to heat the LM335Z, and a really short burst of cooling spray to go below the zero, then finger pressure to heat up again.
I'll post the LM334Z code soon, too. The LM334Z is nicer in that you can trim for 1.65v zero point, so you can use the 'zoom' ADC ranges of the P2
zip
843B
Comments
Nom nom nom. All I think about is P2 Quick Bytes anymore.
KG