Low-Power UART Performs IrDA Link Functions

The functions of a PC-compatible UART and an IrDA interface circuit are combined in the TSS4550 integrated interface device. With a parallel 8-bit bus, the TSS4550 interface can connect to popular microcontrollers with buses from 8 to 32 bits. On-chip receive and transmit FIFOs optimize CPU performance usage while sustaining full-duplex communication at speeds of up to 115.2 kb/s. The device operates from input voltages from 2.7V to 5.5V and consumes just 3 mW at 3V.In the device, one UART is integrated with two modem ports, which can be dynamically switched for flexible connectivity. An alternate port with an integrated IrDA pulse shaper is also provided, enabling the interface to be directly connected to an infrared transceiver. The transceiver can conform to IrDA 1.2 specifications for dramatic power consumption savings.