FEDL7066-01

ML7066

12/29

5) Fractional spurious

ML7066 maintains the accuracy of the RF clock frequency by fine-tuning the PLL oscillation frequency, which helps lower

the component cost for generating the master clock. The Fractional-N PLL type is used to realize the fine tuning of the PLL

oscillation frequency. We found that this PLL type could cause the fractional spurious depending on the combination of the

reference clock, integer dividing ratio, and fractional dividing ratio. So, depending on the combination of the used

frequencies (channels), a false detection of the RSSI value can occur. The following matrixes show the channel combinations

with a possible false detection.

426MHz Band Channel False Detection Matrix

symbol indicates the combination of the transmission and reception channels by the normal setting.

×symbol indicates the channel combination with a possible false detection.

123

45678

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

1

426.0250

●

2

426.0375

●

3

426.0500

●

4

426.0625

●

5

426.0750

●

6

426.0875

●

7

426.1000

●

8

426.1125

●

9

426.1250

●

10

426.1375

●

11

426.1500

12

426.1625

13

426.1750

14

426.1875

15

426.2000

16

426.2125

17

426.2250

18

426.2375

19

426.2500

×

●

20

426.2625

×

●

21

426.2750

×

●

22

426.2875

×

●

23

426.3000

×

●

24

426.3125

×

●

25

426.3250

×

●

26

426.3375

×

●

27

426.3500

×

●

28

426.3625

×

●

29

426.3750

×

●

30

426.3875

×

●

31

426.4000

×

●

32

426.4125

×

●

33

426.4250

×

●

34

426.4375

×

●

35

426.4500

×

●

36

426.4625

×

●

37

426.4750

×

●

38

426.4875

×

●

39

426.5000

×

●

40

426.5125

×

●

41

426.5250

×

●

42

426.5375

××

●

×

43

426.5500

××

●

×

44

426.5625

×

×●×

45

426.5750

×

×●×

46

426.5875

××

●

×

47

426.6000

×

●

48

426.6125

××

●

×

49

426.6250

×

×●×

50

426.6375

×

×●×

51

426.6500

××

●

×

52

426.6625

××

●

53

426.6750

×

●

54

426.6875

×

●

55

426.7000

×

●

56

426.7125

×

●

57

426.7250

×

●

58

426.7375

×

●

59

426.7500

×

●

60

426.7625

×

●

61

426.7750

×

●

62

426.7875

×

●

63

426.8000

×

●

64

426.8125

×

●

65

426.8250

×

●

66

426.8375

×

●

RX

ch

RX freq.

(MHz)

Signal frequency