Datasheet
Table Of Contents
- 1. General Description
- 2. Electrical Characteristics
- 3. SX1272/73 Features
- 4. SX1272/73 Digital Electronics
- 4.1. The LoRaTM Modem
- 4.2. FSK/OOK Modem
- 4.2.1. Bit Rate Setting
- 4.2.2. FSK/OOK Transmission
- 4.2.3. FSK/OOK Reception
- 4.2.4. Operating Modes in FSK/OOK Mode
- 4.2.5. General Overview
- 4.2.6. Startup Times
- 4.2.7. Receiver Startup Options
- 4.2.8. Receiver Restart Methods
- 4.2.9. Top Level Sequencer
- 4.2.10. Data Processing in FSK/OOK Mode
- 4.2.11. FIFO
- 4.2.12. Digital IO Pins Mapping
- 4.2.13. Continuous Mode
- 4.2.14. Packet Mode
- 4.2.15. io-homecontrol® Compatibility Mode
- 4.3. SPI Interface
- 5. SX1272/73 Analog & RF Frontend Electronics
- 6. Description of the Registers
- 7. Application Information
- 8. Packaging Information
- 9. Revision History
www.semtech.comPage 52
SX1272/73
WIRELESS, SENSING & TIMING DATASHEET
Rev. 2 - July 2014
©2014 Semtech Corporation
Table 22 Receiver Startup Time Summary
TS_RE or later after setting the device in Receive mode, any incoming packet will be detected and demodulated by the
transceiver.
4.2.6.3. Time to RSSI Evaluation
The first RSSI sample will be available TS_RSSI after the receiver is ready: equivalently TS_RE + TS_RSSI after the
receive mode instruction was issued.
Figure 19. Time to Rssi Sample
TS_RSSI depends on the receiver bandwidth as well as the RssiSmoothing option that was selected. The formula used to
calculate TS_RSSI is provided in section
5.5.4.
RxBw if AfcAutoOn=0
RxBwAfc if AfcAutoOn=1
TS_RE
(+/-5%)
2.6 kHz 2.33 ms
3.1 kHz 1.94 ms
3.9 kHz 1.56 ms
5.2 kHz 1.18 ms
6.3 kHz 984 us
7.8 kHz 791 us
10.4 kHz 601 us
12.5 kHz 504 us
15.6 kHz 407 us
20.8 kHz 313 us
25.0 kHz 264 us
31.3 kHz 215 us
41.7 kHz 169 us
50.0 kHz 144 us
62.5 kHz 119 us
83.3 kHz 97 us
100.0 kHz 84 us
125.0 kHz 71 us
166.7 kHz 85 us
200.0 kHz 74 us
250.0 kHz 63 us
FSRx
Rx
Rssi IRQ
Rssi sample
ready
Timeline
0TS_RE TS_RE
+TS_RSSI