CN-0109

Circuit Note

Rev. 0 | Page 2 of 3

slew rate. Note that rms jitter values consistently less than 1 ps

can be achieved using the AD9858 circuit.

These circuits must be constructed on multilayer PC boards

with large area ground planes using proper grounding, layout,

and decoupling techniques (see MT-031 Tutorial, Grounding

Data Converters and Solving the Mystery of AGND and DGND

and MT-101 Tutorial, Decoupling Techniques) in order to

achieve these performance levels. Consult the evaluation board

documentation for the AD9958, AD9858, AD9515, and

AD6645 for more guidance.

Product

DDS

Sample

Rate (MHz)

DDS Output

Frequency

(MHz)

DDS Output

Power

(dBm)

DDS

Reconstruction

Filter (MHz)

AD9515

Divider Output

Setting

AD9515 Output

Frequency

(MHz)

Jitter

(rms)

(ps)

AD9958/AD9515

500

38.88

−3.6

200 LPF

1

38.88

4.1

AD9958/AD9515

500

38.88

−3.6

200 LPF

2

19.44

4.1

AD9958/AD9515

500

38.88

−4.7

47 LPF

1

38.88

2.4

AD9958/AD9515

500

38.88

−4.7

47 LPF

2

19.44

2.4

AD9958/AD9515

500

38.88

−3.3

5% BPF

1

38.88

1.5

AD9958/AD9515

500

38.88

−3.3

5% BPF

2

19.44

1.5

AD9958/AD9515

500

77.76

−3.8

200 LPF

1

77.76

2.5

AD9958/AD9515

500

77.76

−3.8

200 LPF

2, 4

38.88, 19.44

2.5

AD9958/AD9515

500

77.76

−4.9

85 LPF

1

77.76

1.5

AD9958/AD9515

500

77.76

−4.9

85 LPF

2, 4

38.88, 19.44

1.5

AD9958/AD9515

500

77.76

−3.8

5% BPF

1

77.76

1.1

AD9958/AD9515

500

77.76

−3.8

5% BPF

2, 4

38.88, 19.44

1.1

AD9958/AD9515

500

155.52

−5.5

200 LPF

2

77.76

1.5

AD9958/AD9515

500

155.52

−5.5

200 LPF

4, 8

38.88, 19.44

1.5

AD9958/AD9515

500

155.52

−5.6

5% BPF

2

77.76

0.68

AD9958/AD9515

500

155.52

−5.6

5% BPF

4, 8

38.88, 19.44

0.68

Product

DDS

Sample

Rate (MHz)

DDS Output

Frequency

(MHz)

DDS Output

Power (dBm)

DDS

Reconstruction

Filter (MHz)

AD9515

Divider Output

Setting

AD9515 Output

Frequency (MHz)

Jitter

(rms)

(ps)

AD9858/AD9515

1000

155.52

+7.7

225 LPF

2

77.76

0.56

AD9858/AD9515

1000

155.52

+7.7

225 LPF

4,8

38.88, 19.44

0.56

AD9858/AD9515

1000

155.52

+7.7

5% BPF

2

77.76

0.33

AD9858/AD9515

1000

155.52

+7.7

5% BPF

4, 8

38.88, 19.44

0.33

AD9858/AD9515

1000

155.52

+2.6

225 LPF

2

77.76

0.63

AD9858/AD9515

1000

155.52

+2.6

225 LPF

4, 8

38.88, 19.44

0.63

AD9858/AD9515

1000

155.52

+1.1

5% BPF

2

77.76

0.42

AD9858/AD9515

1000

155.52

+1.1

5% BPF

4, 8

38.88, 19.44

0.42

AD9858/AD9515

1000

155.52

−3.2

225 LPF

2

77.76

0.73

AD9858/AD9515

1000

155.52

−3.2

225 LPF

4, 8

38.88, 19.44

0.73

AD9858/AD9515

1000

155.52

−4.6

5% BPF

2

77.76

0.64

AD9858/AD9515

1000

155.52

−4.6

5% BPF

4, 8

38.88, 19.44

0.64