Evaluation Board with Resonant PCB Antenna (BIFA)

Si4421

Evaluation Board with Resonant PCB Antenna (BIFA)

Schematics

FFS/DATA SEL SCK SDI

 

 

 

SDO IRQ FFE VDI

 

SDI

 

 

 

CS1

 

 

 

 

 

1

2

 

 

DTO

SCK

 

 

3

4

 

 

VDI

SEL

 

 

5

6

 

 

RESET

DATA

 

 

7

8

 

 

 

VDI

R6

10k

9

10

 

 

DCLK

 

 

11

12

 

 

IRQ

 

R7

100k

13

14

 

 

 

 

 

15

16

 

 

SDO

 

 

 

17

18

 

*

 

 

 

 

19

20

C3

C2

 

 

 

21

22

 

CLKIN

 

 

23

24

 

 

10nF

 

 

25

26

 

 

DATA

 

 

27

28

 

 

 

 

 

29

30

 

 

 

DCLK

R8

10k

31

32

 

 

GND

33

34

 

 

 

 

 

 

DATA

 

 

35

36

 

 

 

 

 

37

38

 

 

 

 

 

 

39

40

 

 

 

 

 

 

 

CON40-0

 

 

 

GND

VDDDual (868/915 MHz)

47/33Manual background C1 Manual background 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

10k

 

 

 

 

 

C6

 

IA4421

 

 

TP3

_OUT

 

 

100pF

 

 

 

 

TP1

CLK

 

 

 

 

 

 

GND

C4 10nFManual background ARSSI

GND

16VDI

15

ARSSI

VDD

 

14

 

 

13

 

L1*

12

 

GND

11

 

 

 

10RESET

9* See values in the table

CLKIN 12 JP1 3 Manual background

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

41

Page 41
Image 41
Silicon Laboratories SI4421 Si4421, Evaluation Board with Resonant PCB Antenna BIFA, Schematics, 868 MHz, Dual 868/915 MHz