OPTICAL TRANSCEIVER WITH IMPROVED RANGE AND DATA COMMUNICATION RATE

摘要

An IR transceiver (10) for use in low-power, lowcost environments such as portable computers and hand-heldcalculators. The transceiver can transmit data at higher,selectable baud rates and at greater distances thanpreviously possible. On the transmitting side thetransceiver elements include a serial interface device(12), encoder circuitry (14) and an IR transmitter (16)with LEDS (34) having fast turn-on and turn-off times. Onthe receiving side are decoder circuitry (20) coupled tothe serial interface device (12) and an IR receiver (18)designed specifically for a photo diode (D1). A baud rategenerator provided by the serial interface device (12)sets the baud rate in the encoding and decoding circuitry(14, 20). The receiver portion of the IR transceiver (10)automatically sets itself to the baud rate of receiveddata. Because of the baud rate selectability, the IRtransceiver (10) is compatible with prior IR transceiversthat are limited to fixed baud rates.