OCCUPANCY-EXP-EVB Silicon Labs

UG376: OCCUPANCY-EXP-EVB Users Guide The Silicon Labs OCCUPANCY-EXP-EVB evaluation kit is an ex- KEY FEATURES pansion board for EFM32 Starter Kits (STKs). The evaluation kit is intended for demonstration and evaluation of an occupancy sens- Quick start demonstration of occupancy sensing and ambient light measurements. ing and ambient light sensing system with Silicon Labs MCU and Discusses the theory of operation and sensor products. implementation considerations of occupancy sensing and ambient light Note: Software examples are provided for the EFM32 Pearl Gecko12 Starter Kit sensing systems. SLSTK3402A (sold separately). Provides performance summary and testing methodologies for evaluating systems. Compatible with SLSTK3402A EFM32 PG12 starter kit. SOFTWARE FEATURES Firmware Code Energy Profiler PIR GUI silabs.com Building a more connected world. Rev. 1.0 Table of Contents 1. Introduction................................3 1.1 Getting Started..............................3 2. Kit Block Diagram .............................4 3. Kit Hardware Layout ............................5 4. Theory of Operation.............................6 4.1 PIR Sensor & Optical Design .........................7 4.2 Analog Signal Amplification and Filtering .....................9 4.3 Signal Digitization and Detection........................11 4.4 Additional Occupancy Sensing Considerations ...................12 4.4.1 Power Supply Design ..........................12 4.4.2 Performance Improvements........................12 4.5 Ambient Light Sensing ...........................13 5. Test Results............................... 14 5.1 Occupancy Sensing ............................14 5.1.1 Detection Sensitivity...........................14 5.1.2 Noise Immunity ............................14 5.1.3 Power Measurement ..........................15 5.2 Ambient Light Sensing ...........................15 5.2.1 Accuracy ..............................15 5.2.2 Power Measurement ..........................16 6. Hardware Details ............................. 17 6.1 Schematics...............................17 6.2 Bill of Materials..............................17 6.3 Assembly Drawings ............................17 6.4 Gerber Files...............................17 6.5 Expansion Header.............................18 7. Software Details ............................. 20 7.1 Importing the Firmware Example........................20 7.2 PIR GUI Details..............................21 8. Kit Revision History and Errata .......................22 8.1 Revision History .............................22 8.2 Errata.................................22 9. Revision History ............................. 23 silabs.com Building a more connected world. Rev. 1.0 2