RadioWire®FSK Transceiver Selection Guide................................................................................................................4
Ordering Information .........................................................................................................................................................4
Pin Configuration...............................................................................................................................................................4
Pin Description...................................................................................................................................................................4
Block Diagram....................................................................................................................................................................6
Absolute Maximum Ratings..............................................................................................................................................7
Operating Ratings..............................................................................................................................................................7
Electrical Characteristics ..................................................................................................................................................7
Functional Description ....................................................................................................................................................10
Control (3-wire) Interface ......................................................................................................................................10
Reading.................................................................................................................................................................13
Control Interface Timing........................................................................................................................................14
Power-on Reset ....................................................................................................................................................14
Clock Generation .............................................................................................................................................................15
Crystal Oscillator (XCO) ..................................................................................................................................................16
BITSYNC_CLK (Receiver Bit Synchronization Clock)..........................................................................................17
BITRATE_CLK (Transmitter Bit Rate Clock) ........................................................................................................17
MODULATOR_CLK (VCO Modulator Clock)........................................................................................................17
Data Interface and Bit Synchronization.........................................................................................................................17
Sync_en = 0 ..........................................................................................................................................................19
Sync_en = 1 ..........................................................................................................................................................19
Additional Considerations in the Use of Synchronizer (Sync_en = 1)..................................................................19
Frequency Synthesizer....................................................................................................................................................20
VCO.......................................................................................................................................................................22
Charge Pump........................................................................................................................................................22
PLL Filter...............................................................................................................................................................22
Lock Detect ...........................................................................................................................................................23
Receiver ............................................................................................................................................................................24
Front End...............................................................................................................................................................24
Sallen-Key Filters..................................................................................................................................................25
Switched Capacitor Filter......................................................................................................................................25
RSSI......................................................................................................................................................................25
FEE .......................................................................................................................................................................26
XCOtune Procedure Example.........................................................................................................................................27
Transmitter........................................................................................................................................................................28
Power Amplifier.....................................................................................................................................................28
Frequency Modulation...........................................................................................................................................29
Divider Modulation ................................................................................................................................................30
VCO Modulation and the Modulator......................................................................................................................30
Modulator Filter .....................................................................................................................................................32
System Modes and Initialization.....................................................................................................................................33
Start-up and Initialization.......................................................................................................................................33
Modes of Operation...............................................................................................................................................33
Mode Transitions...................................................................................................................................................33
Message Coding and Formatting ...................................................................................................................................34
DC Balanced Line Coding.....................................................................................................................................34
Message Formatting: Preamble............................................................................................................................34
Typical Application ..........................................................................................................................................................35
