Dual UART with 16 Bytes Transmit and Receive FIFO


  • Pin to pin and functionally compatible to XR68C681 and SCC68692
  • Full duplex transmit and receive operation
  • 16 bytes of transmit/receive FIFOs (XR68C192)
  • Programmable character lengths (5, 6, 7, 8)
  • Parity, framing, and over run error detection
  • Programmable 16-bit timer/counter
  • On-chip crystal oscillator
  • Single interrupt output with eight selectable interrupting conditions
  • External 1X or 16X clock
  • Data rate up to 1Mbps
  • Independent transmit and receive baud rates from 50bps to 230.4kbps
  • 6 General purpose inputs
  • 8 General purpose outputs
  • TTL-compatible inputs, outputs
  • 4 Transmit/receive trigger levels
  • Watch dog timer
  • Multi-drop mode compatible with 8051 nine bit mode
  • 3.3 or 5 volts operation
  • Loopback modes
  • Power down mode
  • Pb-Free, RoHS Compliant Versions Offered

  • Portable Appliances
  • Telecommunication Network Routers
  • Ethernet Network Routers
  • Cellular Data Devices
  • Factory Automation and Process Controls

The XR68C192 is a Dual Universal Asynchronous Receiver and Transmitter with 16 (XR68C192) bytes transmit and receive FIFO. The XR68C192 is a pin and functional compatible for the XR68C681 and Philips SCC68681 UART with additional features. The operating speed of the receiver and transmitter can be selected independently from a table of twenty four fixed baud rates, a 16X clock derived from a programmable counter/timer, or an external 1X or 16X clock. The baud rate generator and counter/timer can operate directly from a crystal or from external clock input.

The XR68C192 provides a power down mode in which the oscillator is stopped but the register contents are retained. The XR68C192 is fabricated in an advanced CMOS process to achieve low power and high speed requirements.

For UART technical support or to obtain an IBIS model for this product, please email Exar's UART Technical Support group.

Part NumberPkg CodeRoHSMin
StatusBuy NowOrder Samples

Part Status Legend
Active - the part is released for sale, standard product.
EOL (End of Life) - the part is no longer being manufactured, there may or may not be inventory still in stock.
CF (Contact Factory) - the part is still active but customers should check with the factory for availability. Longer lead-times may apply.
PRE (Pre-introduction) - the part has not been introduced or the part number is an early version available for sample only.
OBS (Obsolete) - the part is no longer being manufactured and may not be ordered.
NRND (Not Recommended for New Designs) - the part is not recommended for new designs. 
CPU InterfaceMotorola
Max Data Rate @ 5/3.3/2.5/1.8V (Mbps)1/0.5/na/na
Tx/Rx FIFO (Bytes)16/16
Tx/Rx FIFO CtrsNo
Tx/Rx FIFO INT Trig4 Levels/ 4 Levels
IrDa SupNo
5V Tol InputsYes
Sup V2.97-5.5
PkgsPLCC-44, LQFP-44
Data Rate @ 5/3.3/2.5V1/0.5/na