
MPC9229
MOTOROLA
TIMING SOLUTIONS
6
Programming the MPC9229
Programming the MPC9229 amounts to properly
configuring the internal PLL dividers to produce the desired
synthesized frequency at the output. The output frequency
can be represented by this formula:
fOUT =(fXTAL ÷ 16) (4 M) ÷ (4 N) or
(1)
fOUT =(fXTAL ÷ 16) M ÷ N(2)
where fXTAL is the crystal frequency, M is the PLL
feedback-divider and N is the PLL post-divider. The input
frequency and the selection of the feedback divider M is limited
by the VCO-frequency range. fXTAL and M must be configured
to match the VCO frequency range of 800 to 1600 MHz in
order to achieve stable PLL operation:
MMIN =4fVCO,MIN ÷ fXTAL and
(3)
MMAX =4fVCO,MAX ÷ fXTAL
(4)
For instance, the use of a 16 MHz input frequency requires
the configuration of the PLL feedback divider between M=200
and M = 400. Table 7 shows the usable VCO frequency and
M divider range for other example input frequencies.
Assuming that a 16 MHz input frequency is used, equation (2)
reduces to:
fOUT =M ÷ N(5)
Table 7. MPC9229 Frequency Operating Range
VCO frequency for an crystal interface frequency of
Output frequency for fXTAL=16 MHz and for N =
M
M[8:0]
10
12
14
16
18
20
1
2
4
16
160
010100000
800
170
010101010
850
180
010110100
810
900
190
010111110
855
950
200
011001000
800
900
1000
200
100
50
25
210
011010010
840
945
1050
210
105
52.5
26.25
220
011011100
880
990
1100
220
110
55
27.50
230
011100110
805
920
1035
1150
230
115
57.5
28.75
240
011110000
840
960
1080
1200
240
120
60
30
250
011111010
875
100
1125
1250
250
125
62.5
31.25
260
100000100
910
1040
1170
1300
260
130
65
32.50
270
100001110
810
945
1080
1215
1350
270
135
67.5
33.75
280
100011000
840
980
1120
1260
1400
280
140
70
35
290
100100010
870
1015
1160
1305
1450
290
145
72.5
36.25
300
100101100
900
1050
1200
1350
1500
300
150
75
37.5
310
100110110
930
1085
1240
1395
1550
310
155
77.5
38.75
320
101000000
800
960
1120
1280
1440
1600
320
160
80
40
330
101001010
825
990
1155
1320
1485
330
165
82.5
41.25
340
101010100
850
1020
1190
1360
1530
340
170
85
42.5
350
101011110
875
1050
1225
1400
1575
350
175
87.5
43.75
360
101101000
900
1080
1260
1440
360
180
90
45
370
101110010
925
1110
1295
1480
370
185
92.5
46.25
380
101111100
950
1140
1330
1520
380
190
95
47.5
390
110000110
975
1170
1365
1560
390
195
97.5
48.75
400
110010000
1000
1200
1400
1600
400
200
100
50
410
110011010
1025
1230
1435
420
110100100
1050
1260
1470
430
110101110
1075
1290
1505
440
110111000
1100
1320
1540
450
111000010
1125
1350
1575
510
111111110
1275
1530