SM1211E915TOPIC Semtech, SM1211E915TOPIC Datasheet - Page 32

• Manufacturer Part Number: SM1211E915TOPIC
• Description: KIT PICTAIL EXT FOR SX1211
• Manufacturer: Semtech
• Type: Transceiver, UHFr

Specifications of SM1211E915TOPIC

• Frequency: 915MHz
• For Use With/related Products: SX1211
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

For proper operation, the Bit Synchronizer must first receive three bytes of alternating logic value preamble, i.e.
“0101” sequences. After this startup phase, the rising edge of DCLK signal is centered on the demodulated bit.
Subsequent data transitions will preserve this centering.
This has two implications:
This implies approximately 6 consecutive unbalanced bytes when the Bit Rate precision is 1%, which is easily
achievable (crystal tolerance is in the range of 50 to 100 ppm).
Bit Synchronizer and Active channel filter settings are a function of the reference oscillator crystal frequency, F
Settings other than those programmable with a 12.8 MHz crystal can be obtained by selection of the correct
reference oscillator frequency. Please contact your local Semtech representative for further details.
After OOK or FSK demodulation, the baseband signal is made available to the user on pin 20, DATA, when
Continuous mode is selected.
In Buffered and Packet modes, the data is retrieved from the FIFO through the SPI interface.
Rev 7 – Sept 2
ADVANCED COMMUNICATIONS & SENSING
Firstly, if the Bit Rates of Transmitter and Receiver are known to be the same, the SX1211 will be able to
receive an infinite unbalanced sequence (all “0s” or all ”1s”) with no restriction.
If there is a difference in Bit Rate between Tx and Rx, the amount of adjacent bits at the same level that the
BitSync can withstand can be estimated as:
3.4.12. Alternative Settings
3.4.13. Data Output
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NumberOfBi
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SX1211
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