DAN-191 Datasheet, PDF (2/3 Pages) Exar Corporation – EXAR UARTS IN BLUETOOTH APPLICATIONS

DAN191
EXAR UARTS IN BLUETOOTH APPLICATIONS
4.0 XR20M1170 IN BLUETOOTH APPLICATIONS
Exar’s XR20M1170 is a single channel I2C/SPI UART and it is ideal for Bluetooth applications for the reasons
listed below. Since the SPI mode supports a 5MHz clock and the I²C interface only supports up to 400kHz, the
SPI mode is recommended to achieve the highest performance.
FIGURE 2. XR20M1170 BLUETOOTH APPLICATIONS SOLUTION BLOCK DIAGRAM
SPI Bus
Master
3 Mbps
SPI
XR20M1170
UART
UART
MCU
115.2 Kbps
Bluetooth
Module/
Chipset
4.1 High Performance
The XR20M1170 can easily support the 3Mbps data rate requirement. If necessary, the XR20M1170 can
support UART serial data rates of up to 16Mbps. Data throughput and interrupt servicing can be optimized by
utilizing the 64 byte TX and RX FIFOs.
4.2 Low Voltage Operation
The XR20M1170 can operation from 1.62V - 3.63V to directly interface with the lower voltage MCUs as well as
the lower voltage Bluetooth chipsets.
4.3 Low Power Consumption
The XR20M1170 has a sleep mode to minimize the power consumption. In the sleep mode, the XR20M1170
consumes less than 30 uA. This will significantly help extend the battery life of the handheld/portable
applications.
4.4 Small Package Size
The XR20M1170 is available in a 4x4mm QFN package which will require minimal board space.
4.5 Fractional Baud Rate Generator and 8X/4X Sampling Rate
In addition, with the combination of the Fractional Baud Rate Generator and 8X/4X sampling rate features, the
XR20M1170 can take any existing clock source on the board (above 12MHz) to generate the 3Mbps UART
data rate which further saves valuable PCB space.
5.0 CONCLUSION
With its low power consumption, small package size and enhanced features, Exar’s XR20M1170 is the ideal
solution for communication between an MCU and a Bluetooth module/chipset.
2