2.25V to 3.6V Quad UART with 32-Byte FIFO

  • Pin-to-pin compatible with ST16C454, ST16C554, TI’s TL16C754B and Philips' SC16C754B
  • Intel or Motorola Data Bus Interface select
  • Four independent UART channels
  • Register Set Compatible to 16C550
  • Data rates of up to 16 Mbps
  • 32 byte Transmit FIFO
  • 32 byte Receive FIFO with error tags
  • 4 Selectable TX and RX FIFO Trigger Levels
  • Automatic Hardware (RTS/CTS) Flow Control
  • Automatic Software (Xon/Xoff) Flow Control
  • Programmable Xon/Xoff characters
  • Wireless Infrared (IrDA 1.0) Encoder/Decoder
  • Full modem interface
  • 2.25V to 3.6V supply operation
  • Sleep Mode with automatic wake-up
  • Crystal oscillator or external clock input
  • Pb-Free, RoHS Compliant Versions Offered

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

The XR16V5641 (V564) is an enhanced quad Universal Asynchronous Receiver and Transmitter (UART) with 32 bytes of transmit and receive FIFOs, programmable transmit and receive FIFO trigger levels, automatic hardware and software flow control, and data rates of up to 16 Mbps at 4X sampling rate. Each UART has a set of registers that provide the user with operating status and control, receiver error indications, and modem serial interface controls. An internal loopback capability allows onboard diagnostics. The V564 is available in a 48-pin QFN, 64-pin LQFP, 68-pin PLCC and 80-pin LQFP packages. The 64-pin and 80-pin packages only offer the 16 mode interface, but the 48 and 68 pin packages offer an additional 68 mode interface which allows easy integration with Motorola processors. The XR16V564IV (64-pin) offers three state interrupt output while the XR16V564DIV provides continuous interrupt output. The XR16V564 is compatible with the industry standard ST16C554 and ST16C654/654D.

1Covered by U.S. Patent #5,649,122.

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 InterfaceIntel or Motorola
Max Data Rate @ 5/3.3/2.5/1.8V (Mbps)na/16/12.5/na
Tx/Rx FIFO (Bytes)32/32
Tx/Rx FIFO CtrsNo
Tx/Rx FIFO INT Trig4 Levels/ 4 Levels
IrDa SupYes
5V Tol InputsYes
Sup V2.25-3.6
PkgsPLCC-68, LQFP-64, QFN-48, LQFP-80
Data Rate @ 5/3.3/2.5Vna/16/12.5