AN2648

Summary

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Summary

The STLM20 is very accurate over a wide temperature range and has a nearly linear output

which spans the voltage range 2.33 down to 0.87 volts over the corresponding temperature

range –40° to +85°C. While it can be directly connected to an 8-bit A-D converter such as

those often found integrated into low-cost microcontrollers, the resolution may be too coarse

for some applications, amounting to –1.677°C per A-D step. For applications requiring

higher resolution, users can use an op-amp and a voltage reference to add gain and offset

to the STLM20 output. This has the effect of increasing the resolution over the temperature

range of interest while avoiding the need for a more expensive, higher resolution A-D

converter. Using averages of four samples also increases the effective resolution. The final

result is that users can achieve resolution as fine as 0.1°C with the STLM20.