Silicon Laboratories SI4421 Si4421, Evaluation Board with Resonant PCB Antenna BIFA, Schematics

Page 41

Si4421

Evaluation Board with Resonant PCB Antenna (BIFA)

Schematics

FFS/DATA SEL SCK SDI					SDO IRQ FFE VDI
SDI				CS1
SDI			1	2			DTO
SCK			3	4			VDI
SEL			5	6			RESET
DATA			7	8
VDI	R6	10k	9	10			DCLK
VDI			11	12			IRQ
	R7	100k	13	14			IRQ
			15	16			SDO
			17	18		*
			19	20	C3	*	C2
			21	22	C3		C2
CLKIN			23	24			10nF
CLKIN			25	26			10nF
DATA			27	28
DATA			29	30
DCLK	R8	10k	31	32			GND
	R8	10k	33	34
			33	34
DATA			35	36
DATA			37	38
			39	40
				CON40-0

GND

VDD

C1 2.2uF

IC1

SDI		1	SDI	NINT/VDI
SCK		2	SCK	ARSSI
SEL		3	NSEL	VDD
SDO		4	SDO	RF1
IRQ		5	NIRQ	RF2
DATA		6	FSK/DATA/NFFS VSS
DCLK		7	DCLK/CFIL	NRES
DTO	R5	8	CLK	XTL/REF
DTO	10k	8	CLK	XTL/REF
	10k
	C6		IA4421
	TP3	_OUT	IA4421
	100pF
	TP1	CLK
		CLK

GND

C4 10nF ARSSI

GND

16VDI

15	ARSSI	VDD
15	ARSSI
14
13		L1*
12		GND
11		GND
11

10RESET

9* See values in the table

CLKIN 12 JP1 3

Q1	10MHz
	GND

Note: Components R5 to R8 and C6 are needed for connection to the ISM Chipset Development Kit load board (IA ISM-DK3) and are not necessary in an application.

Frequency Dependent Component Values

Band	C3 [pF]	L1 [nH]
868 MHz	47	22
Dual (868/915 MHz)	47/33	18
915 MHz	33	15

Image 41

Contents FEATURES FUNCTIONAL BLOCK DIAGRAMDESCRIPTION TYPICAL APPLICATIONSRF Power Amplifier PA DETAILED FEATURE-LEVELDESCRIPTIONData Filtering and Clock Recovery Si4421Wake-UpTimer Low Battery Voltage DetectorData Validity Blocks Crystal OscillatorName Si4421 PACKAGE PIN DEFINITIONSType FunctionInternal Pin Connections Si4421Name Internal connectionPIN10 Logic Diagram nRES I/O PIN6 Logic Diagram FSK / DATA / nFFSNote These pins can be left floating Si4421Typical Application Si4421Recommended supply decoupling capacitor values Pin Function vs. Operation ModeRecommended Operating Range Si4421 GENERAL DEVICE SPECIFICATIONSAbsolute Maximum Ratings non-operating Si4421 ELECTRICAL SPECIFICATIONDC Characteristics Si4421 AC Characteristics PLL parametersAC Characteristics Receiver AC Characteristics Transmitter Si4421AC Characteristics Turn-on/Turnaroundtimings AC Characteristics OthersNote 10 By design Si4421Timing Diagram Si4421 CONTROL INTERFACETiming Specification Si4421 Control CommandsControl Register Default Values Configuration Setting Command Description of the Control Commands2. Power Management Command Si4421Si4421 Logic connections between power control bits4. Data Rate Command Frequency Setting Command5. Receiver Control Command Si4421Si4421 VDI Logic DiagramSi4421 6. Data Filter CommandSi4421 7.FIFO and Reset Mode Command9. Receiver FIFO Read Command 8. Synchron Pattern Command10. AFC Command Si4421Bit 5-4rl1 to rl0 Si4421Si4421 11. TX Configuration Control CommandFrequency Setting Command Si4421 13. Transmitter Register Write Command12. PLL Setting Command Si4421 14. Wake-UpTimer Command15.Low Duty-CycleCommand Si4421 Vlb= 2.25 + V · 0.1 V Clock divider configurationBit Name 17. Status Read CommandSi4421 Si4421 INTERRUPT HANDLING Si4421 TX REGISTER BUFFERED DATA TRANSMISSIONTypical TX register usage Si4421RECOMMENDED PACKET STRUCTURES Si4421 RX FIFO BUFFERED DATA READBit Rate 2.4 kbps Si4421 CRYSTAL SELECTION GUIDELINESBit Rate 9.6 kbps Bit Rate 38.4 kbpsSi4421 RX-TXALIGNMENT PROCEDURES Si4421 RESET MODES FIFO and Reset Mode Command page Sensitive Reset Enabled, Ripple on VddSW Reset Command Si4421Channel Selectivity and Blocking Si4421 TYPICAL PERFORMANCE CHARACTERISTICSBER Curves in 868 MHz Band Si4421BER Curves in 433 MHz Band 434 MHz Si4421Schematics Si4421 REFERENCE DESIGNSEvaluation Board with 50 Ohm Matching Network Frequency Dependent Component ValuesPCB Layout Top View Bottom View Si4421Si4421 SchematicsEvaluation Board with Resonant PCB Antenna BIFA Frequency Dependent Component ValuesTop View Bottom View Si4421PCB Layout Antenna designed for 868/915 MHz band See Detail “A” Section B-B Si4421 PACKAGE INFORMATION16-pinTSSOP Si4421 Universal ISM Band FSK Transceiver RELATED PRODUCTS AND DOCUMENTSDemo Boards and Development Kits Related ResourcesSi4421

Evaluation Board with Resonant PCB Antenna (BIFA)

Dual (868/915 MHz)

47/33