JetPLL Technology

Jitter Reduction - JetPLL™

JetPLL™ is a patented jitter elimination technology concerned not only with peak-to-peak jitter, but also the spectral distribution of the jitter. Whenever a digital system interfaces with the analog world, time has to be presented precisely, or the theories for sampling (Nyquist) will be invalid. In the digital world, time is discrete and as such represented by a number or a distinct event. In the interface to the real continuous world, any imprecision in time will result in an error in the conversion.

The error will manifest itself in different ways depending on the character of the jitter and the application. In an A to D or D to A application, "white" jitter will result in reduced dynamic range (in the case of extracting clocks from an asynchronous network such as IEEE1394, USB, or AVB, this could reduce the dynamic range to 60dB or less if care is not taken). In the same application, discrete jitter will result in side-bands or inter-modulation distortion which means the system will "invent" frequencies unrelated to the actual signal.

For audio applications, jitter will reduce the overall quality of the signal. It will reduce the dynamic range, reduce or smear stereo imaging, and in extreme cases create "computer-sounding" audio.

For industrial applications, jitter can create uncertainty in the time-stamping of events and create false spikes in the frequency domain, masking other important information or resulting in misinterpretation of data from, for example, a vibration sensor.

Who needs JetPLL™?

Any application relying on interfacing time-based information between the digital and the analog world will benefit from jitter reduction. This includes any application using AD or DA converters, including PWM modulators.

AES Convention paper on the benefits of JetPLL 1.0