Datasheet

Data Sheet AD9559
Rev. C | Page 25 of 120
Figure 27. Closed-Loop Transfer Function for 100 Hz, 2 kHz, and 5 kHz Loop
Bandwidth Settings; High Phase Margin Loop Filter Setting
(This figure is compliant with Telcordia GR-253
jitter transfer test for loop bandwidths < 2 kHz.)
Note that bandwidth is defined as the point where the open loop gain = 0 dB.
Figure 28. Closed-Loop Transfer Function for 100 Hz and 2 kHz Loop
Bandwidth Settings; Normal Phase Margin Loop Filter Setting
Note that bandwidth is defined as the point where the open loop gain = 0 dB.
–30
–27
–24
–21
–18
–15
–12
–9
–6
–3
0
3
10 100 1k 10k 100k
FREQUENCY OFFSET (Hz)
LOOP GAIN (dB)
10644-129
LOOP BW = 100Hz;
HIGH PHASE MARGIN;
PEAKING: 0.06dB; –3dB: 69Hz
LOOP BW = 2kHz;
HIGH PHASE MARGIN;
PEAKING: 0.097dB; –3dB: 1.23kHz
LOOP BW = 5kHz;
HIGH PHASE MARGIN;
PEAKING: 0.14dB; –3dB: 4.27kHz
–30
–27
–24
–21
–18
–15
–12
–9
–6
–3
0
3
10 100 1k
FREQUENCY OFFSET (Hz)
LOOP GAIN (dB)
10k 100k
10644-230
LOOP BW = 100Hz;
NORMAL PHASE MARGIN;
PEAKING: 0.09dB; –3dB: 117Hz
LOOP BW = 2kHz;
NORMAL PHASE MARGIN;
PEAKING: 1.6dB; –3dB: 2.69kHz