CDCM6208V1RGZT datasheet(56/78 Pages) TI

Part #	CDCM6208V1RGZT

Description	2:8 CLOCK GENERATOR, JITTER CLEANER WITH FRACTIONAL DIVIDERS

Download	78 Pages

Scroll/Zoom	100%

Manufacturer	TI [Texas Instruments]

Direct Link	http://www.ti.com

Logo

56 / 78 page

CDCM6208

SCAS931A – MAY 2012 – REVISED JUNE 2012

www.ti.com

When the output frequency plan calls for the use of some output dividers as fractional values, the following steps

are needed to calculate the closest achievable frequencies for those using fractional output dividers and the

frequency errors (difference between the desired frequency and the closest achievable frequency).

•

Based on system needs, decide the frequencies that need to have best possible jitter performance.

•

Once decided, these frequencies need to be placed on integer output dividers.

•

Then a frequency plan for these frequencies with strict jitter requirements can be worked out using the

common divisor algorithm.

•

Once the integer divider plans are worked out, the PLL settings (including VCO frequency, feedback divider,

input divider and prescaler divider) can be worked out to map the input frequency to the frequency out of the

prescaler divider.

•

Then calculate the fractional divider values (whose values must be greater than 2) that are needed to support

the output frequencies that are not part of the common frequency plan from the common divisor algorithm

already worked out.

•

For each fractional divider value, try to represent the fractional portion in a 20 bit binary scheme, where the

first fractional bit is represented as 0.5, the second fractional bit is represented as 0.25, third fractional bit is

represented as 0.125 and so on. Continue this process until the entire 20 bit fractional binary word is

exhausted.

•

Once exhausted, the fraction can be calculated as a cumulative sum of the fractional bit x fractional value of

the fractional bit. Once this is done, the closest achievable output frequency can be calculated with the

mathematical function of the frequency out of the prescaler divider divided by the achievable fractional

divider.

•

The frequency error can then be calculated as the difference between the desired frequency and the closest

achievable frequency.

56

Submit Documentation Feedback

Product Folder Link(s): CDCM6208

Similar Part No. - CDCM6208V1RGZT

Manufacturer	Part #	Datasheet	Description
Texas Instruments	CDCM6208V1RGZT	2Mb / 92P	[Old version datasheet] 2:8 Clock Generator, Jitter Cleaner With Fractional Dividers

More results

Similar Description - CDCM6208V1RGZT

Manufacturer	Part #	Datasheet	Description
Texas Instruments	CDCM6208V1F	2Mb / 87P	[Old version datasheet] 2:8 Clock Generator, Jitter Cleaner with Fractional Dividers
	CDCM6208	2Mb / 89P	[Old version datasheet] 2:8 Clock Generator, Jitter Cleaner With Fractional Dividers
	CDCM6208	2Mb / 92P	[Old version datasheet] 2:8 Clock Generator, Jitter Cleaner With Fractional Dividers
	CDCM6208V2G	2Mb / 88P	[Old version datasheet] CDCM6208V2G 2:8 Clock Generator, Jitter Cleaner with Fractional Dividers
Analog Devices	AD9523	1,011Kb / 60P	Jitter Cleaner and Clock Generator
Analog Devices	AD9524	973Kb / 56P	Jitter Cleaner and Clock Generator
Texas Instruments	CDCE62002	1Mb / 49P	[Old version datasheet] Four Output Clock Generator/Jitter Cleaner With Integrated Dual VCOs
	LMK04100	588Kb / 46P	[Old version datasheet] Clock Jitter Cleaner with Cascaded PLLs
	LMK04100	1Mb / 52P	[Old version datasheet] Family Clock Jitter Cleaner
	CDCE62005	2Mb / 80P	[Old version datasheet] Five/Ten Output Clock Generator/Jitter Cleaner With Integrated Dual VCOs

More results

CDCM6208V1RGZT Datasheet(PDF) 56 Page - Texas Instruments

CDCM6208V1RGZT Datasheet(HTML) 56 Page - Texas Instruments

Similar Part No. - CDCM6208V1RGZT

Similar Description - CDCM6208V1RGZT

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78

Datasheet Download

Link URL