SX1308
WIRELESS & SENSING PRODUCTS Datasheet
V1.2 June 2017 www.semtech.com 2
Contents
1 PIN CONFIGURATION .................................................................................................................. 4
1.1 Pins Placement and Circuit Marking ........................................................................................... 4
1.2 Pins Description .......................................................................................................................... 5
2 ELECTRICAL CHARACTERISTICS ................................................................................................... 7
2.1 Absolute Maximum Ratings ........................................................................................................ 7
2.2 Constraints on External ............................................................................................................... 7
2.3 Operating Conditions .................................................................................................................. 7
2.4 Electrical Specifications ............................................................................................................... 8
2.5 Timing Specifications .................................................................................................................. 8
3 CIRCUIT OPERATION ................................................................................................................... 9
3.1 General Presentation .................................................................................................................. 9
3.2 Power-On .................................................................................................................................... 9
3.2.1 Power-Up Sequence ................................................................................................................ 9
3.2.2 Setting the Circuit is Low-Power Mode .................................................................................. 9
3.3 Clocking ..................................................................................................................................... 10
3.4 SPI Interface .............................................................................................................................. 11
3.5 Rx I/Q Interface ......................................................................................................................... 12
3.5.1 I/Q Generated on Clock Rising Edge ..................................................................................... 12
3.5.2 I/Q Generated on Clock Falling Edge .................................................................................... 12
3.6 RX Mode Block Diagram, Reception Paths Characteristics ....................................................... 13
3.6.1 Block Diagram ....................................................................................................................... 13
3.6.2 Reception Paths Characteristics ............................................................................................ 14
3.7 Packet Engine and Data Buffers ................................................................................................ 15
3.7.1 Receiver Packet Engine ......................................................................................................... 15
3.7.2 Transmitter Packet Engine .................................................................................................... 17
3.8 Receiver IF Frequencies Configuration ..................................................................................... 19
3.8.1 Configuration Using 2 x SX1257 Radios ................................................................................ 19
3.8.2 Two SX1255: 433 MHz Band ................................................................................................. 21
3.8.3 One SX1257 and one SX1255 ................................................................................................ 21
3.9 Connection to RF Front End ...................................................................................................... 22
3.9.1 Connection to Semtech SX1255 or SX1257 Components ..................................................... 22
3.9.2 SX1308 RX Operation Using a Third Party RF Front End ....................................................... 22
3.9.3 Radio Calibration ................................................................................................................... 24
3.9.4 SX1308 Connection to RF Front End for TX Operation ......................................................... 24
3.10 Reference Application ............................................................................................................... 26
3.11 Hardware Abstraction Layer (HAL) ........................................................................................... 27
3.11.1 Introduction .......................................................................................................................... 27
3.11.2 Abstraction Presented to the Gateway Host ........................................................................ 27
4 EXTERNAL COMPONENTS ......................................................................................................... 29
5 PCB LAYOUT CONSIDERATIONS ................................................................................................ 30
6 PACKAGING INFORMATION ...................................................................................................... 32
6.1 Package Outline Drawing .......................................................................................................... 32
6.2 Thermal Impedance of Package ................................................................................................ 32
6.3 Land Pattern Drawing ............................................................................................................... 33
7 REVISION INFORMATION .......................................................................................................... 34