User's Guide
SLAU417–December 2011
AFE4110 Thermometer Demonstration Board
This user’s guide provides a general description of the AFE4110 thermometer demonstration board
(demo-pen). Use this document with the AFE4110 data sheet to get a broader understanding of the
functions and applications of this device.
Contents
1 Hardware Description ...................................................................................................... 1
2 Getting Started .............................................................................................................. 3
2.1 Inserting Battery and Reading the LCD Display ............................................................... 3
2.2 Board Jumper Configuration ...................................................................................... 4
3 Electrical Characteristics ................................................................................................... 4
4 Schematics and Layout .................................................................................................... 4
4.1 Schematics .......................................................................................................... 4
4.2 Layouts .............................................................................................................. 5
5 Bill of Materials .............................................................................................................. 6
List of Figures
1 AFE4110 Thermometer Demonstration Board Front (Bottom Layer) and Back (Top Layer) ..................... 2
2 Firmware Flowchart......................................................................................................... 3
3 Inserting Battery Into Holder............................................................................................... 4
4 Measured Temperature Accuracy vs Temperature..................................................................... 4
5 Top Layer Copper........................................................................................................... 5
6 Bottom Layer Copper....................................................................................................... 5
7 Silk Screen Top ............................................................................................................. 5
8 Silk Screen Bottom ......................................................................................................... 5
List of Tables
1 Description of Main Board Components ................................................................................. 2
2 Bill of Materials.............................................................................................................. 6
1 Hardware Description
Figure 1 shows the front and back sides of the thermometer. The board demonstrates an accurate,
low-cost, single-chip temperature measurement solution based on the AFE4110. This device is a
general-purpose, low-cost, 1.5-V microcontroller optimized for this application with features like an internal
1.85-V/3.3-V charge-pump for LCD/GPIO interface, buzzer driver, low-power sleep mode, etc. See the
AFE4110 data sheet (SLLSE48) for further details.
The measurement is done using an external thermistor with a negative temperature coefficient (NTC)
characteristic (resistance decreases with increasing temperature). The thermistor response has been
calibrated using two temperature points (at 31°C and 43°C), for an overall typical accuracy of ±0.1°C over
that range, when measured in a calibration bath. The system has not been designed to measure human
body temperature and must not be used for health diagnosis purposes.
1
SLAU417–December 2011 AFE4110 Thermometer Demonstration Board
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