MPC9229 REVISION 5 DECEMBER 19, 2012

6

©2012 Integrated Device Technology, Inc.

MPC9229 Data Sheet

400MHZ LOW VOLTAGE PECL CLOCK SYNTHESIZER

PROGRAMMING INTERFACE

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 = 4 fVCO,MIN  fXTAL and

(3)

MMAX = 4 fVCO,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

Table 7. MPC9229 Frequency Operating Range

M

M[8:0]

VCO frequency for a crystal interface frequency of

Output frequency for fXTAL = 16 MHz and for N =

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