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CDCE6214-Q1: Output Clock Pull Range

Rolf Wietelmann
Prodigy 10 points
Part Number: CDCE6214-Q1
Other Parts Discussed in Thread: CDCE6214,

Tool/software:

What we need:
A single output device (multiple outputs are great but given the requirements below we suspect we'd need to consume an entire device due to pulling/changing the VCO freq). 
Output clock  freq:  pullable/variable "live"  (smooth, glitch-free freq transitions)   from 100Mhz to 96Mhz  (upper value range might possibly be slightly less)
Freq change step sizes.      N* (Xppm)  ,   N = 1-50  (1-100 better) ,   X = 0.3ppm   (possibly as large as 1ppm we'd have to test how much larger than 0.3ppm is acceptable). 
Max  Freq Change Slew Rate :   1 Hz / uSec  (1Mhz/sec),    2 Hz / uS  preferred.   (in practice we perform freq steps every 1-8mS)  
1) Can we meet these requirements with a  CDCE6214 ?  (we also need autoqual).
2)  Is there a configuration tool for TI clock devices? 
  • 0
    TI__Mastermind 22670 points

    Rolf,

    I believe that you can best achieve this behavior with CDCE6214-Q1. The TICS Pro GUI (https://www.ti.com/tool/TICSPRO-SW) is best for configuring this device.

    The relevant section from the datasheet for DCO mode control is here (for determining register settings):

    The DCO can be adjusted using either I2C access or through configuring two GPIO pins for DCO Increment and DCO Decrement.

    Thanks,

    Kadeem

  • 0 in reply to Kadeem Samuel
    Prodigy 10 points

    Thank you Kathleen.

    I forgot to clarify one aspect of operation.

    It seems to me from the documentation (data sheet)  that freq changes via  DCO  modify the root VCO operating frequency and hence modify ALL output clock frequencies - is this correct?

    Also I assume the full pull range of DCO operation is determined by the available adjustment range of the  sigma-delta modulator numerator value. 

    Is that range clearly specified in the data sheet ?  (I will look for that info...)

    Will the TICS Pro Gui program assist in determining (output)  max-min  pull range  for DCO operation as function of step-size setting?

    Thanks again,

    Rolf

  • 0 in reply to Rolf Wietelmann
    TI__Expert 6135 points

    Closing thread for now to consolidate discussion to email.

    Best,

    Cris