The ST16C554/554D is a full-duplex serial communication controller developed by EXAR Corporation, which supports 16-byte FIFO, multiple interface modes and multiple interrupt control modes. It can be widely used in network devices, data terminals, industrial control and consumer electronics.
The ST16C554/554D is a universal asynchronous receiver‑transmitter (UART) that provides four independent UART channels, each with 16‑byte transmit and receive FIFOs and error‑flag support. It operates from 2.97 V to 5.5 V and supports data rates up to 1.5 Mbps (24 MHz clock). The device includes selectable Intel (16‑mode) or Motorola (68‑mode) bus interfaces and a range of interrupt and modem control signals.
The UART is offered in 68‑lead PLCC and 64‑lead LQFP packages, with operating temperature ranges of 0 °C to +70 °C (standard) or –40 °C to +85 °C for extended‑temperature versions. Detailed pin‑out tables, block diagrams for both interface modes, and ordering information are provided in the document.
| Supply Voltage | 2.97 V to 5.5 V |
|---|---|
| Maximum Data Rate | 1.5 Mbps (24 MHz) |
| Transmit FIFO Size | 16 bytes |
| Receive FIFO Size | 16 bytes with error flags |
| Standard Operating Temperature | 0 °C to +70 °C |
| Extended Operating Temperature | -40 °C to +85 °C |
It operates from 2.97 V up to 5.5 V.
The device can transmit and receive up to 1.5 Mbps when driven by a 24 MHz clock.
Both the transmit and receive FIFOs hold 16 bytes; the receive FIFO also provides error flags.