MAX31820(3)

power

read-only,yes-no
Is the chip powered externally (=1) or from the parasitically from the data bus (=0)?

temperature

read-only, floating point
Measured temperature with 12 bit resolution.

temperature9 temperature10 temperature11 temperature12

read-only, floating point
Measured temperature at 9 to 12 bit resolution. There is a tradeoff of time versus accuracy in the temperature measurement.

latesttemp

read-only, floating point
Measured temperature at 9 to 12 bit resolution, depending on the resolution of the latest conversion on this chip. Reading this node will never trigger a temperature conversion. Intended for use in conjunction with /simultaneous/temperature.

fasttemp

read-only, floating point
Equivalent to temperature9

See the file man3/temperature_threshold.3so.

See the file man3/temperature_resolution.3so.

See the file man3/temperature_errata.3so.

DS18B20

The DS18B20 (3) is one of several available 1-wire temperature sensors. It is the replacement for the DS18S20 (3) Alternatives are DS1822 (3) as well as temperature/voltage measurements in the DS2436 (3) and DS2438 (3). For truly versatile temperature measurements, see the protean DS1921 (3) Thermachron (3).

The MAX31820 is functionally identical to the DS18B20 except for it's voltage requirements.
The DS18B20 (3) can select between 4 resolutions. In general, high resolution is the best choice unless your application is truly time-constrained.