AN498 Datasheet, PDF (1/58 Pages) Silicon Laboratories – Infrared Gesture Sensing

AN498
Si114X DESIGNER’S GUIDE
1. Introduction
This application note provides an outline for using the Si114x proximity detector and ambient-light sensor. General
considerations of electrical and optical component selection, programming, and power consumption are explained
so as to cover the majority of situations. Specific topics are discussed elsewhere:
AN521: IRLED Selection Guide for Si114x Proximity Applications
AN522: Using the Si1141 for Touchless Lavatory Appliances
AN523: Overlay Considerations for the Si114x Sensor
AN540: Hair Immune Cheek Detection in SmartPhones Using the Si1141 Infrared Sensor
AN541: Smoke Detection using the C8051F990 and Si1141
AN580: Infrared Gesture Sensing
2. Optical Considerations toward Mechanical Design
This section focuses on mechanical and industrial design considerations.
2.1. Topology
Figure 1 highlights and defines the various system topologies.
Si114
irLED
No Overlay
a) No Port
Preliminary Rev. 0.7 1/15
Sensor and emitter
underneath a single
compartment, single
overlay
b) Single Port
Overlay
Si114
Overlay
irLED
Emitter and sensor are in
separate compartments,
each compartment has a
separate overlay.
c) Dual Port
Overlay
Emitter and sensor are
underneath one overlay,
Si114
irLED
but with an optical block
in-between. The Hybrid is
essentially a Single-port
d) Hybrid ^{with optical blocking}
Figure 1. System Topologies
Copyright © 2015 by Silicon Laboratories
AN498