Digital circuits at high frequency?.......

[walkman]

Hi,

i am currently working on high speed interconnects i want to why we cant operate(use) digital circuits at high frequencies(ex:15Ghz)and why we are going for analog circuits for high frequencies?

Thanks in advance.

 

[dragonfury]

Hi,

i am currently working on high speed interconnects i want to why we cant operate(use) digital circuits at high frequencies(ex:15Ghz)and why we are going for analog circuits for high frequencies?

Thanks in advance.

Are you referring to the High-Speed Transmitter/Receiver for I/O interfaces or are you referring to core Transmitter/Receiver?

 

[kripacharya]

digital circuits are composite circuit blocks using switching elements of various types. Each of these elements has a capacitance of some amount which CANNOT be reduced below some minimum limit (depends on the technology). Hence the circuits are unable to 'switch' faster than a corresponding maximum.

This is also one of the reasons that lower switching voltages are used to help speed things up.

 

[walkman]

Dragonfury,
i am taking about core Transmitter/Receiver in HSS ser/des ckts