TRC105 RFM, TRC105 Datasheet - Page 47

• Manufacturer Part Number: TRC105
• Description: IC TXRX 300MHZ-510MHZ 32TQFN
• Manufacturer: RFM

Specifications of TRC105

• Frequency: 300MHz ~ 510MHz
• Data Rate - Maximum: 200kbps
• Modulation Or Protocol: FSK, OOK
• Applications: General Purpose
• Power - Output: 13dBm
• Sensitivity: -112dBm
• Voltage - Supply: 2.1 V ~ 3.6 V
• Current - Receiving: 3mA
• Current - Transmitting: 30mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFN
• Wireless Frequency: 300 MHz to 510 MHz
• Output Power: 13 dBm
• Operating Supply Voltage: 2.1 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Maximum Supply Current: 1.7 mA
• Minimum Operating Temperature: - 40 C
• Modulation: FSK, OOK
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 583-1159-2

C must be an integer value, so BR is limited to 256 discrete values. If the value of C given in the above equation
is not an integer for your desired bit rate, round the value of C down to the nearest integer. You can then calculate
the nearest available bit rate equal to or greater than your desired bit rate.
Selection of the RF data rate allows a suitable FSK deviation to be determined. This, in turn, allows the configura-
tion value for the anti-aliasing filters in the transmitter and the configuration values for the R-C and Butterworth
low-pass filters in the receiver to be determined.
The minimum required deviation for good TRC105 FSK performance is:
Where F
mended deviation is ±33 kHz, even at low data rates. F
the standard crystal frequency of 12.8 MHz:
Where F
R must be an integer value, so F
is not an integer for your desired deviation, round the value of R down to the nearest integer and use this value to
meet or exceed the minimum required deviation for the bit rate you are using.
Once BR and F
can be determined. The recommended 3 dB bandwidth (cutoff frequency) for the transmitter anti-aliasing filters is:
Where F
kHz and BR is the bit rate in kb/s. F
quency of 12.8 MHz:
Where F
pattern in TXCFG1A bits 7..4. Solving the equation above for K:
K must be an integer value, so F
not an integer for your desired deviation, round the value of K down to the nearest integer and use this value to
set the bandwidth of the transmitter anti-aliasing filters. For operation at 90 kb/s and above, use a value of 15
for K.
The recommended 3 dB bandwidth for the receiver Butterworth filters is:
Where F
is the bit rate in kb/s. This equation assumes use of the high accuracy, low drift XTL1020 crystal. If an alternative
crystal is used, add ½ the expected drift due to temperature and aging to the equation above. F
with bits 3..0 in RXCFG10. For the standard crystal frequency of 12.8 MHz:
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©2009-2010 by RF Monolithics, Inc.
F
F
R = (12800 - 32*F
F
F
K = (F
F
F
DEV
DEV
CTX
CTX
CBW
DEV
DEV
CTX
CTX
CBW
CBW
is the deviation in kHz and BR is the bit rate in kb/s. Specific to the TRC105, the minimum recom-
is the deviation in kHz. Solving the equation above for R:
is the 3 dB bandwidth of the transmitter anti-aliasing filters in kHz, F
is the 3 dB bandwidth of the transmitter anti-aliasing filters in kHz and K is the integer value of the bit
is the 3 dB bandwidth of the Butterworth filters in kHz, F
= 3*F
= 200*(K + 1)/8, with K in the range of 0 to 15
= BR
= 12800/(32*(R + 1)), with the useable range of R 1 to 11
E-mail:
= 2*F
= 200*(J + 1)/8, with J in the range of 0 to 15
CTX
DEV
- 25)/25
DEV
DEV
have been determined, the bandwidths and related configuration values for the TRC105 filters
[e-mail]
+ 1.5*BR
+ BR
DEV
)/32*F
CTX
DEV
DEV
CTX
is limited to 16 discrete values. If the value of K given in the above equation is
is limited to 11 discrete values. If the value of R given in the above equation
is configured with bits 7..4 in TXCFG1A. For the standard crystal fre-
Technical support +1.800.704.6079
DEV
is configured with an integer R stored in MCFG02. For
DEV
is the frequency deviation in kHz and BR
DEV
is the frequency deviation in
CBW
TRC105 - 11/01/10
is configured
Page 47 of 66