TH71221_15 Datasheet, PDF (2/44 Pages) Melexis Microelectronic Systems – FSK/FM/ASK Transceiver

TH71221
27 to 930MHz
FSK/FM/ASK Transceiver
Table of Content
1 Theory of Operation ...................................................................................................4
1.1 General .............................................................................................................................. 4
1.2 Technical Data Overview ................................................................................................... 4
1.3 Note on ASK Operation...................................................................................................... 4
1.4 Block Diagram.................................................................................................................... 5
1.5 User Mode Features .......................................................................................................... 5
2 Pin Definitions and Descriptions ..............................................................................6
3 Functional Description ............................................................................................10
3.1 PLL Frequency Synthesizer ............................................................................................. 10
3.1.1 Reference Oscillator (XOSC)..................................................................................................... 11
3.1.2 Reference Divider ...................................................................................................................... 11
3.1.3 Feedback Divider ....................................................................................................................... 11
3.1.4 Frequency Resolution and Operating Frequency ...................................................................... 11
3.1.5 Phase-Frequency Detector ........................................................................................................ 12
3.1.6 Lock Detector ............................................................................................................................. 12
3.1.7 Voltage Controlled Oscillator with external Loop Filter .............................................................. 13
3.1.8 Loop Filter .................................................................................................................................. 13
3.2 Receiver Part ................................................................................................................... 13
3.2.1 LNA ............................................................................................................................................ 14
3.2.2 Mixer .......................................................................................................................................... 14
3.2.3 IF Amplifier ................................................................................................................................. 14
3.2.4 ASK Demodulator ...................................................................................................................... 14
3.2.5 FSK Demodulator ...................................................................................................................... 15
3.3 Transmitter Part ............................................................................................................... 15
3.3.1 Power Amplifier .......................................................................................................................... 15
3.3.2 Output Power Adjustment .......................................................................................................... 16
3.3.3 Modulation Schemes ................................................................................................................. 16
3.3.4 ASK Modulation ......................................................................................................................... 16
3.3.5 FSK Modulation ......................................................................................................................... 17
3.3.6 Crystal Tuning ............................................................................................................................ 17
4 Description of User Modes......................................................................................18
4.1 Stand-alone User Mode Operation ................................................................................... 18
4.1.1 Frequency Selection .................................................................................................................. 18
4.1.2 Operation Mode ......................................................................................................................... 18
4.1.3 Modulation Type ........................................................................................................................ 19
4.1.4 LNA Gain Mode ......................................................................................................................... 19
4.2 Programmable User Mode Operation............................................................................... 19
4.2.1 Serial Control Interface Description ........................................................................................... 19
5 Register Description ................................................................................................20
5.1 Register Overview............................................................................................................ 21
39010 071221
Rev. 009
Page 2 of 44
Data Sheet
Nov/15