MRF49XA Datasheet, PDF (7/102 Pages) Microchip Technology – ISM Band Sub-GHz RF Transceiver

1.0 INTRODUCTION
Microchip Technology’s MRF49XA is a fully integrated
Sub-GHz RF transceiver. This low-power single chip
FSK baseband transceiver supports:
• Zero-IF architecture
• Multi-channel and multi-band
• Synthesizer with Phase Locked Loop (PLL)
• Power Amplifier (PA)
• Low Noise Amplifier (LNA)
• I/Q down converter mixers
• I/Q demodulator
• Baseband filters and amplifiers
The simplified functional block diagram of MRF49XA is
shown in Figure 1-1. The MRF49XA is an ideal choice
for low-cost, high-volume, low data rate (< 256 kbps),
two-way, short range wireless applications. This trans-
ceiver can be used in the unlicensed 433, 868 and
915 MHz frequency bands, and for applications looking
for FCC, IC or ETSI certification in the ISM band.
The MRF49XA has a low phase noise and provides an
excellent adjacent channel interference, Bit Error
Rate (BER) and larger communication coverage along
with higher output power. The MRF49XA device’s
Automatic Frequency Control (AFC) feature allows for
the use of a low-accuracy, low-cost crystal. In order to
minimize the total system cost, a communication link in
most of the applications can be created using a
low-cost, generic 10 MHz crystal, a bypass filter and an
affordable microcontroller. The MRF49XA provides a
clock signal for the microcontroller and avoids the need
for a second crystal on the circuit board. The trans-
ceiver can be interfaced with many popular Microchip
PIC^® microcontrollers via a 4-wire SPI, interrupt (IRO)
and Reset. The interface between the microcontroller
and MRF49XA is shown in Figure 1-2.
MRF49XA
The MRF49XA supports the following digital data
processing features:
• PLL and I/Q VCO with Calibration
• Receiver Signal Strength Indicator
• Data Quality Indicator
• Automatic Frequency Control
• Baseband Power Amplifier
• TX and RX Buffers
The receiver’s Baseband Bandwidth (BBBW) can be
programmed to accommodate various deviations, data
rates and crystal tolerance requirements.
The high-resolution PLL allows:
• The usage of multiple channels in any of the
bands
• The rapid settling time allows for faster frequency
hopping, bypassing multipath fading and
interference to achieve robust wireless links
The transceiver is integrated with different Sleep modes
and an internal wake-up timer to reduce the overall cur-
rent consumption, and to extend the battery life. The
device’s small size with low-power consumption makes
it ideal for various short range radio applications.
© 2009 Microchip Technology Inc.
Preliminary
DS70590B-page 5