What is the difference between a DLL and a PLL?

[dhasmana]

What is the difference between a DLL and a PLL?

 

[normaldist]

One is a method of locking a signal to a reference, the other is a library for Windows functionality.

Seriously, do you mean a DDS, Direct digital systhesis or DLL, Delay locked loop? To lock a frequency to a reference you must create an error for an offset. A PLL divides the output down to the reference for phase comparison. The divide ratio is digital and can let the PLL tune over a wide range of frequencies. A DLL uses delay of the output to create a phase comparison. This typically is not programable and does not allow for wide tuning. A DLL can have some advantages over a PLL interms of noise performance.

 

[melc]

first:
http://www.answers.com/topic/delay-locked-loop
and:
http://en.wikipedia.org/wiki/Phase-locked_loop

then very intuitive the differences between those:
**broken link removed**

do you need more scientific?
http://www.google.com/search?q=delay+locked+loop&hl=en&start=20&sa=N
http://www.google.com/search?hl=en&q=phase+locked+loop