Enhanced UARTs boost efficiency, performance and integration

Exar has introduced the XR20V2172 and XR20M1172 enhanced Universal Asynchronous Receiver-Transmitters (UARTs) that combine capabilities of the industry-standard 16550 UART with additional system-level benefits.

The XR20V2172 integrates an RS-232 transceiver on chip to save component count, footprint and PCB-design overheads. The transceiver meets true EIA/TIA-232-F standards from 2.97V to 3.63V, and can be turned off independently from the UART allowing versatile power management.

The XR20M1172 supports 64bytes of transmit-andreceive FIFO memory, compared to 16bytes in the 16550 architecture. This reduces the FIFO-service load on the host processor, and combines with selectable sampling rates, FIFO-trigger-level control and automatic-flow control to allow data exchanges at up to 16Mbit/s at 3.3V. The XR20M1172 also provides general-purpose I/Os and can be used with a crystal oscillator or external-clock input.

In both UARTs the configuration registers are 16550-compatible, allowing easy integration and application development. Other valuable features include a programmable fractional-baud-rate generator with prescaler, a complete modem interface, on-board status and dataerror registers, and internal loopback supporting system diagnostics.

 

FEATURES Selectable I2C/SPI interface XR20V2172: Operating voltage range: 3.3V to 5.5V 64-pin QFN package XR20M1172: Operating voltage range: 1.62V to 3.6V 32-pin QFN or 28-pin TSSOP package

APPLICATIONS Portable appliances Data loggers Machine-to-machine communications Factory automation and process controls

 

 

 

 

 

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