MCP2120-I/SL: An IrDA Standard-Compliant UART-to-Infrared Encoder/Decoder from Microchip

In the realm of wireless data communication, infrared (IR) technology remains a reliable and cost-effective solution for short-range, line-of-sight data transfer. At the heart of many such systems lies a critical component: the encoder/decoder. The MCP2120-I/SL from Microchip Technology is a standout device in this category, serving as a complete physical layer solution for implementing IrDA standard-compliant infrared data links.

The primary function of the MCP2120 is to seamlessly interface between a standard UART (Universal Asynchronous Receiver/Transmitter) and an infrared transceiver. It takes the asynchronous serial data from a microcontroller's UART, encodes it into a format compliant with the IrDA Physical Layer Specification (version 1.4), and drives an IR LED transmitter. Conversely, it receives the pulsed IR signal from a photodiode receiver, decodes it, and presents standard serial data back to the UART. This functionality effectively bridges the gap between the digital world of a microcontroller and the optical domain of infrared communication.

A key advantage of the MCP2120-I/SL is its simplification of system design. By integrating the complex encoding and decoding logic, including the mandatory 3/16 demodulator for receiving data, it relieves the host microcontroller from this computationally intensive task. This allows designers to implement robust IrDA connectivity without requiring sophisticated software routines or consuming valuable processor cycles. The device supports all standard IrDA data rates from 2.4 kbps up to 115.2 kbps, making it compatible with a wide range of applications and host controller capabilities.

The device is offered in a compact 16-pin SOIC package, making it suitable for space-constrained applications. It operates over a broad voltage range of 2.0V to 5.5V, ensuring compatibility with both 3V and 5V microcontroller systems. Typical applications extend beyond computer peripherals like printers and PDAs to include point-of-sale (POS) terminals, medical devices, test equipment, and industrial control systems where reliable, short-distance wireless data exchange is required.

ICGOODFIND: The MCP2120-I/SL is an elegant and highly integrated solution for developers seeking to add standardized infrared communication to their designs. Its ability to handle the entire IrDA physical layer protocol transparently, combined with its low power consumption and small form factor, makes it an excellent choice for simplifying hardware design and accelerating time-to-market for a multitude of consumer and industrial products.

Keywords: IrDA Standard, UART Interface, Infrared Encoder/Decoder, Short-Range Communication, Physical Layer