CN8330EPD CONEXANT [Conexant Systems, Inc], CN8330EPD Datasheet - Page 100

• Manufacturer Part Number: CN8330EPD
• Description: DS3/E3 Framer with 52 Mbps HDLC Controller
• Manufacturer: CONEXANT [Conexant Systems, Inc]

Appendix C
C-2
voltage/frequency conversion ratio (Ko) parameter measured in radians per
second per volt. In our PLL loop filter calculations, Ko equals approximately
400 for a VCXO with +/- 200 ppm pullability. Given Ko, a 10Hz break frequency
is calculated for R1=R2=500K. With a 10Hz break, attenuation at 100Hz is
around -12dB, barely sufficient to meet 0.4UI output jitter required with 1.5UI
input and 0.08UI intrinsic jitter.
successfull results using R1=R2=1M. While this LPF should work for both T3
and E3 applications, we have not tested the PLL to comply with any regulatory or
interface requirements. LPF cutoff frequencies might have to be scaled to match
desired loop timing characteristics or to have the desired cutoff frequency. We
recommend all customers conduct performance evaluation and characterization
testing of the PLL before sending equipment for certification.
The overall jitter transfer function also depends on the VCXO control
For added margin, R1=R2=1M puts the break frequency at 7Hz.
Several CN8330 customers have tested the jitter attenuation PLL with
Conexant
DS3/E3 Framer with 52 Mbps HDLC Controller
CN8330
100441E