RFM213W Datasheet, PDF (13/20 Pages) List of Unclassifed Manufacturers – Low-Cost Consumer Electronics Applications

Category
(G)FSK
Settings
Decode
Settings
Parameters
Descriptions
Peak Drop Rate
The RSSI peak drop rate, the options are: 1 step/4
symbols, 1 step/2 symbols, 1 step /1 symbol, or 1
step/0.5 symbol.
AGC
Automatic Gain Control, the options are: on or off.
Deviation
The (G)FSK frequency deviation. The minimum value
of the deviation is equal to Xtal Tolerance (ppm) x
Frequency (MHz) / 0.7. The maximum value of
deviation is equal to 220 kHz - Xtal Tolerance (ppm) x
Frequency (MHz).
Data
Representation
To select whether the frequency “Fo + Fdev”
represent data 0 or 1. The options are: 0: F-high
1:F-low, or 0: F-low 1:F-high.
Sync Clock Type
This parameter allows the user to select the method to
perform the clock data recovery. The options are:
tracing or counting.
Rising Relative TH
This is the relative threshold to trigger the (G)FSK
demodulation. It is measured in terms of RSSI code.
The options are: 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30,
36, 42, 54, 66, or 90.
Falling Relative TH
This is the relative threshold to shut down the (G)FSK
demodulation. It is measured in terms of RSSI code.
The range is from 0 to 255.
Turn on/off the Automatic Frequency Control function.
AFC
The options are: On or Off.
Preamble
The size of the valid preamble, the options are: 1-byte,
2-byte, 3-byte, or 4-byte.
RFM213W
Default
Mode
1 step /
4 symbols
Advanced
On
Advanced
35 kHz
Basic
Advanced
0: F-low
1:F-high
Basic
Advanced
Counting
Advanced
21
Advanced
255
On
2-byte
Advanced
Advanced
Advanced
5.5 Internal Blocks Description
5.5.1 RF Front-end and AGC
The RFM213W features a low-IF receiver. The RF front-end of the receiver consists of a Low Noise Amplifier (LNA), I/Q mixer
and a wide-band power detector. Only a low-cost inductor and a capacitor are required for matching the LNA to any common
used antennas. The input RF signal induced on the antenna is amplified and down-converted to the IF frequency for further
processing.
By means of the wide-band power detector and the attenuation networks built around the LNA, the Automatic Gain Control (AGC)
loop regulates the RF front-end’s gain to get the best system linearity, selectivity and sensitivity performance, even though the
receiver suffers from strong out-of-band interference.
5.5.2 IF Filter
The signals coming from the RF front-end are filtered by the fully integrated 3^rd-order band-pass image rejection IF filter which
achieves over 35 dB image rejection ratio typically. The IF center frequency is dynamically adjusted to enable the IF filter to
locate to the right frequency band, thus the receiver sensitivity and out-of-band interference attenuation performance are kept
optimal despite the manufacturing process tolerances. The IF bandwidth is automatically computed according to the three basic
system parameters input from the RFPDK: RF frequency, Xtal tolerance, and symbol rate.
E‐mail:[e-mail] website://www.hoperf.com
Rev 1.0 | Page 13/21