AN2648 Datasheet, PDF (1/15 Pages) STMicroelectronics – Increasing the resolution of analog temperature sensors

AN2648
Application note
Increasing the resolution of analog temperature sensors
Introduction
For a recent trade show, a demonstration board was required to display ST's new low-cost
temperature sensor, the STLM20. The idea was to connect it to a basic microcontroller with
on-board analog-to-digital converter (ADC) and display the temperature on seven-segment
LEDs. Any user would be able to affect the temperature by applying his finger directly to the
sensor and then watch the display change as a result.
The goal was to keep things simple and use the ADC converter on the micro thus avoiding
the expense and engineering effort of using an external ADC.
Using the STLM20 temperature sensor with low-cost microcontrollers
The design flow used for the demonstration board can be applied in many applications. This
document describes how any user can implement a temperature sensor design using the
LM20 and a low-cost microcontroller with integral A-D converter.
Figure 1. STLM20 demonstration board
34mm / 1.34
200mm / ~8
144mm / 5.7
280mm / ~11
December 2007
Rev 1
1/15
www.st.com