XR20M1170 Datasheet, PDF (1/60 Pages) Exar Corporation – I2C/SPI UART WITH 64-BYTE FIFO

XR20M1170
I2C/SPI UART WITH 64-BYTE FIFO
MAY 2007
REV. 1.0.0
GENERAL DESCRIPTION
The XR20M1170¹ (M1170) is a high performance
universal asynchronous receiver and transmitter
(UART) with 64 byte TX and RX FIFOs and a
selectable I²C/SPI slave interface. The M1170
operates from 1.62 to 3.63 volts. The enhanced
features in the M1170 include a programmable
fractional baud rate generator, an 8X and 4X
sampling rate that allows for a maximum baud rate of
16 Mbps at 3.3V. The standard features include 16
selectable TX and RX FIFO trigger levels, automatic
hardware (RTS/CTS) and software (Xon/Xoff) flow
control, and a complete modem interface. Onboard
registers provide the user with operational status and
data error flags. An internal loopback capability
allows system diagnostics. The M1170 is available in
the 28-pin QFN, 24-pin QFN, 16-pin QFN, 24-pin
TSSOP and 16-pin TSSOP packages. The 28-pin
QFN package has the EN485# and ENIR# pins to
allow the UART to power-up in the Auto RS485 mode
or the Infrared mode.
NOTE: 1 Covered by U.S. Patent #5,649,122
APPLICATIONS
• Portable Appliances
• Battery-Operated Devices
• Cellular Data Devices
• Factory Automation and Process Controls
FEATURES
• 1.62 to 3.6 Volt Operation
• Selectable I²C/SPI Interface
• Full-featured UART
■ Data rate of up to 16 Mbps at 3.3 V
■ Data rate of up to 12.5 Mbps at 2.5 V
■ Data rate of up to 8 Mbps at 1.8 V
■ Fractional Baud Rate Generator
■ Transmit and Receive FIFOs of 64 bytes
■ 16 Selectable TX and RX FIFO Trigger Levels
■ Automatic Hardware (RTS/CTS) Flow Control
■ Automatic Software (Xon/Xoff) Flow Control
■ Halt and Resume Transmission Control
■ Automatic RS-485 Half-duplex Direction
Control Output via RTS#
■ Wireless Infrared (IrDA 1.0 and 1.1) Encoder/
Decoder
■ Automatic sleep mode (< 15 uA at 3.3V)
■ General Purpose I/Os
■ Full modem interface
• Crystal oscillator (up to 24MHz) or external clock
(up to 64MHz) input
• 28-QFN, 24-QFN, 16-QFN, 24-TSSOP, 16-TSSOP
packages
FIGURE 1. XR20M1170 BLOCK DIAGRAM
VCC
ENIR#
EN485#
IRQ#
SDA
SCL
A0/CS#
A1/SI
SO
I2C/SPI#
1.62V – 3.63V
I²C/SPI
Interface
UART
Regs
64 Byte
TX FIFO
64 Byte
RX FIFO
BRG
GPIOs
Crystal Osc/Buffer
TX
RX
RTS#
CTS#
GPIO[7:0]
XTAL1
XTAL2
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • [phone] • FAX [phone] • www.exar.com