The XR16M654/654D is a quad Universal Asynchronous Receiver and Transmitter (UART) from Exar Corporation that supports data rates of up to 16 Mbps and includes automatic hardware and software flow control and FIFO buffers.
The XR16M654/654D is a quad universal asynchronous receiver‑transmitter (UART) from Exar, operating from 1.62 V to 3.63 V and offering 64‑byte transmit and receive FIFOs for each of its four independent channels.
It supports data rates up to 16 Mbps, provides selectable Intel or Motorola bus interfaces, and is offered in multiple packages (48‑pin QFN, 64‑pin LQFP, 68‑pin PLCC, 80‑pin LQFP, 100‑pin QFP). The device is compatible with standard ST16C554 and ST16C654/654D parts and includes various interrupt and flow‑control features.
| Supply voltage | 1.62 V to 3.63 V |
|---|---|
| Maximum data rate | up to 16 Mbps |
| FIFO depth per channel | 64 bytes transmit, 64 bytes receive |
| FIFO depth per channel | 64 bytes receive |
| Number of UART channels | 4 |
| Compatibility | ST16C554, ST16C654/654D |
| Interrupt output mode | continuous (XR16M654DIV) or three‑state (XR16M654IV) |
The device operates from 1.62 V to 3.63 V.
It provides four independent UART channels.
It supports data rates of up to 16 Mbps.