SWRS046H – NOVEMBER 2006 – REVISED MARCH 2015
Table 5-12. Typical PLL Turn-on Time to Within ±10% of Channel Spacing for Different Loop Filter
Bandwidths
C6
C7
C8
R2
R3
PLL TURN-ON TIME
COMMENT
[nF]
[pF]
[pF]
[k
Ω
]
[k
Ω
]
[µs]
Up to 4.8 kBaud data
rate,
220
8200
2200
1.5
4.7
3200
12.5 kHz channel
spacing
Up to 4.8 kBaud data
100
3900
1000
2.2
6.8
2500
rate,
25 kHz channel spacing
Up to 9.6 kBaud data
56
2200
560
3.3
10
1400
rate,
50 kHz channel spacing
Up to 19.2 kBaud data
15
560
150
5.6
18
1300
rate,
100 kHz channel spacing
Up to 38.4 kBaud data
3.9
120
33
12
39
1080
rate,
150 kHz channel spacing
Up to 76.8 kBaud data
1.0
27
3.3
27
82
950
rate,
200 kHz channel spacing
Up to 153.6 kBaud data
0.2
1.5
—
47
150
700
rate,
500 kHz channel spacing
5.12.4 PLL Lock Time Versus Loop Filter Bandwidth
If calibration has been performed the PLL lock time is the time needed for the PLL to lock to the desired
frequency when going from RX to TX mode or vice versa. The PLL lock time depends on the PLL loop
filter bandwidth.
gives the PLL lock time for different PLL loop filter bandwidths.
Table 5-13. Typical PLL Lock Time to Within ±10% of Channel Spacing for Different Loop Filter
Bandwidths
(1)
PLL LOCK TIME [µs]
C6
C7
C8
R2
R3
Comment
[nF]
[pF]
[pF]
[k
Ω
]
[k
Ω
]
1
2
3
Up to 4.8 kBaud data rate, 12.5 kHz
220
8200
2200
1.5
4.7
900
180
1300
channel spacing
Up to 4.8 kBaud data rate, 25 kHz
100
3900
1000
2.2
6.8
640
270
830
channel spacing
Up to 9.6 kBaud data rate, 50 kHz
56
2200
560
3.3
10
400
140
490
channel spacing
Up to 19.2 kBaud data rate, 100 kHz
15
560
150
5.6
18
140
70
230
channel spacing
Up to 38.4 kBaud data rate, 150 kHz
3.9
120
33
12
39
75
50
180
channel spacing
Up to 76.8 kBaud data rate, 200 kHz
1.0
27
3.3
27
82
30
15
55
channel spacing
Up to 153.6 kBaud data rate, 500
0.2
1.5
—
47
150
14
14
28
kHz channel spacing
(1)
1) 307.2 kHz step,
2) 1 channel step,
3) 1 MHz step
50
Detailed Description
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