The ST16C654CJ is a quad-channel UART (Universal Asynchronous Receiver/Transmitter) manufactured by Exar Corporation. The 'CJ' likely refers to the package type, though without further information, it's hard to determine definitively. This device provides four independent serial communication channels on a single chip, making it well-suited for applications requiring multiple serial interfaces.

Applications

• Multi-port serial cards
• Industrial automation controllers
• Communication servers
• Embedded systems with multiple serial interfaces
• Data acquisition systems
• Point-of-Sale (POS) systems

Features

• Quad UART channels
• Data rates up to 5 Mbps per channel
• Programmable baud rate generator for each channel
• 32-byte FIFO (First-In, First-Out) transmitter and receiver buffers for each channel
• Automatic hardware/software flow control for each channel
• Modem control signals (CTS, RTS, DSR, DTR, RI, DCD) for each channel
• Interrupt generation
• Loopback mode for diagnostics

Benefits

• Quad-channel capability: Provides four independent serial communication channels, maximizing serial connectivity while minimizing component count.
• High-speed data transmission: Supports data rates up to 5 Mbps per channel, enabling fast and efficient serial communication.
• Reduced CPU overhead: The 32-byte FIFOs significantly reduce CPU intervention, improving overall system performance.
• Flexible baud rate generation: Programmable baud rate generator allows for a wide range of baud rates to be selected for each channel, accommodating diverse communication standards.
• Reliable data transfer: Automatic flow control ensures reliable data transfer by preventing buffer overflow on each channel.
• Easy integration: The standard UART interface simplifies integration into existing systems.
• Diagnostic capabilities: Loopback mode enables easy testing and troubleshooting of each channel.

Additional Details

The ST16C654CJ operates from a single 5V power supply. It supports 5, 6, 7, or 8 data bits, with even, odd, or no parity, and 1 or 2 stop bits for each of its four channels. The 'CJ' package is likely a surface-mount package for efficient PCB assembly. The inclusion of 32-byte FIFOs is a key advantage over the ST16C554 series, providing superior data handling and reduced CPU interaction.

Its compliance with industry-standard UART protocols ensures a versatile solution for many serial communication applications. The larger internal FIFO buffers and flow control features enable robust and efficient data handling, crucial for reliable system operation when managing multiple serial connections. The quad channels facilitate concurrent communication with up to four distinct serial devices, while the larger FIFOs improve performance under high data loads.