User manual

MCP3421 WEIGHT SCALE
DEMO BOARD USER’S GUIDE
 2010 Microchip Technology Inc. DS51918A-page 3
Table of Contents
Preface ........................................................................................................................... 5
Chapter 1. Product Overview
1.1 Overview ........................................................................................................ 9
1.2 Analog Input Configuration Options ............................................................. 10
1.3 Load Cell ...................................................................................................... 11
1.4 Universal Serial Bus (USB) and PIC18F4550 Microcontroller ..................... 12
1.5 What the MCP3421 Weight Scale Kit Contains ........................................... 12
Chapter 2. Installation and Operation
2.1 MCP3421 Configuration Bit Settings and Data Acquisition .......................... 13
2.2 USB Communication .................................................................................... 13
Chapter 3. Weight Scale PC Software Tool
3.1 Software Installation ..................................................................................... 15
3.2 Software Overview ....................................................................................... 15
3.3 Weight Scale Calibration .............................................................................. 16
Appendix A. Schematics and Layouts
A.1 Introduction .................................................................................................. 17
A.2 Board – Schematic ....................................................................................... 18
A.3 Board – Top Copper and Pads .................................................................... 19
A.4 Board – Top Pads and Silk .......................................................................... 20
A.5 Board – Top Copper, Pads and Silk ............................................................ 21
A.6 Board – Bottom Copper and Pads ............................................................... 22
Appendix B. Bill of Materials
Worldwide Sales and Service .................................................................................... 26