IrDA Transceiver Selection Guide

This guide helps in selecting the right IrDA transceiver from various manufacturers. We’ll cover what an IrDA transceiver is and what specifications to consider.

What is an IrDA Transceiver?

Introduction:

An IrDA transceiver is a transceiver that uses the IrDA (Infrared Data Association) protocol and light as its communication medium. Think of it as a wireless version of a serial cable, using infrared light instead of wires.

Figure 1 shows a comparison between wired communication (using RS232) and wireless communication using an IrDA transceiver (like the Microchip MCP21xx).

Figure 1: Wireless configuration using IrDA Transceiver

IR stands for Infrared, which utilizes frequencies ranging from 300 GHz to 400 THz, with wavelengths from 1 mm to 750 nm. IR-based devices facilitate communication between devices like PDAs, laptops, mobile phones, and computers, typically over distances of 10 to 30 meters.

Figure 2: Infrared communication modes

IR devices support two main communication modes:

• Point-to-Point: Requires a direct Line of Sight (LOS) between the transmitter and receiver.
• Diffuse: Doesn’t necessarily require a LOS connection.

IrDA Transceiver Selection Guide

When choosing an IrDA transceiver for your application, consider the following specifications:

• Data Rate: Common options include 115.2 Kbps, 1.152 Mbps, 4 Mbps, and 16 Mbps. Choose one that meets your bandwidth needs.
• Voltage Supply: Transceivers operate at different voltages (e.g., 1.7V to 2.5V). Make sure it’s compatible with your system.
• Idle Current: The amount of current the transceiver draws when not actively transmitting. Lower is better for power saving, measured at 25°C.
• Link Range: The maximum communication distance in centimeters (cm). This depends on the application requirements.
• Peak Wavelength: Measured in nanometers (nm), determines the specific infrared wavelength used.
• Radiant Intensity: Measured in milliwatts per steradian (mWatt/Sr), indicates the power of the emitted infrared light.
• Orientation: The physical orientation of the transceiver (Side View, Top View, or Universal) will dictate how it’s mounted in your device.
• Operating Temperature: The temperature range within which the transceiver will function correctly.
• Standards Supported: Different IrDA standards exist (IrDA 1.2, IrDA 1.3, IrDA 1.4, etc.). Ensure compatibility with the devices you need to communicate with.
• Package Type: Available in various formats like Cut Tape, Digi-Reel™, Tape & Reel, and Tube for different assembly processes.

IrDA Transceiver Manufacturers

Here’s a list of popular IrDA Transceiver manufacturers:

• Zilog
• Vishay
• Sharp Microelectronics
• Rohm Semiconductor
• Panasonic Electronic Components
• Lite-On Inc.
• Texas Instruments
• Linear Technology
• Cypress Semiconductor
• Maxim Integrated
• Broadcom
• Cirrus Logic