SX1231
DATASHEET
Page
ADVANCED COMMUNICATIONS & SENSING
Table of Contents
1.
General Description ................................................................................................................................................ 8
1.1.
Simplified Block Diagram ................................................................................................................................ 8
Pin and Marking Diagram ................................................................................................................................ 9
Pin Description .............................................................................................................................................. 10
1.2.
1.3.
2.
Electrical Characteristics....................................................................................................................................... 11
2.1.
ESD Notice.................................................................................................................................................... 11
Absolute Maximum Ratings .......................................................................................................................... 11
Operating Range........................................................................................................................................... 11
Chip Specification ......................................................................................................................................... 12
2.2.
2.3.
2.4.
2.4.1. Power Consumption ................................................................................................................................. 12
2.4.2. Frequency Synthesis................................................................................................................................ 12
2.4.3. Receiver ................................................................................................................................................... 13
2.4.4. Transmitter ............................................................................................................................................... 14
2.4.5. Digital Specification ...................................................................................................................................15
Chip Description.................................................................................................................................................... 16
3.
3.1.
Power Supply Strategy.................................................................................................................................. 16
Low Battery Detector..................................................................................................................................... 16
Frequency Synthesis..................................................................................................................................... 16
3.2.
3.3.
3.3.1. Reference Oscillator................................................................................................................................. 16
3.3.2. CLKOUT Output ........................................................................................................................................17
3.3.3. PLL Architecture....................................................................................................................................... 17
3.3.4. Lock Time ..................................................................................................................................................18
3.3.5. Lock Detect Indicator................................................................................................................................ 18
3.4.
Transmitter Description ................................................................................................................................. 19
3.4.1. Architecture Description ........................................................................................................................... 19
3.4.2. Bit Rate Setting ........................................................................................................................................ 19
3.4.3. FSK Modulation........................................................................................................................................ 20
3.4.4. OOK Modulation....................................................................................................................................... 20
3.4.5. Modulation Shaping.................................................................................................................................. 21
3.4.6. Power Amplifiers ...................................................................................................................................... 21
3.4.7. Over Current Protection ........................................................................................................................... 21
3.5.
Receiver Description ..................................................................................................................................... 22
3.5.1. Block Diagram .......................................................................................................................................... 22
3.5.2. LNA - Single to Differential Buffer ............................................................................................................ 22
3.5.3. Automatic Gain Control ............................................................................................................................ 23
3.5.4. Quadrature Mixer - ADCs - Decimators.................................................................................................... 24
3.5.5. Channel Filter........................................................................................................................................... 25
3.5.6. DC Cancellation ....................................................................................................................................... 26
3.5.7. Complex Filter - OOK ............................................................................................................................... 26
3.5.8. RSSI......................................................................................................................................................... 26
Rev 2 - Nov 2009
Page 2
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