Time to Digital Converter

Lizwi · Nov 9, 2023

Hi
I am doing a masters project in electronics.
My project is titled "Time to Digital Converter"

I am trying to understand the working of a delay line:

1. How does a delay line differ from a counter?
2. What is the need to delay a start signal and how does that improves the time resolution for a TDC?

Thanks

Delta Prime · Nov 9, 2023

Lizwi said:
I am doing a masters project in electronics.
My project is titled "Time to Digital Converter"

I am trying to understand the working of a delay line:

A masters? I would love to have that sheepskin. Good luck to you.
Here's a snippet.
Delay line based time-to-digital converter: This is a very primitive TDC and involves a delay-line which is used to delay the reference signal. The other signal is used to sample the state of delay chain. Each stage of delay chain outputs to a flip-flop or a latch which is clocked by the sample signal.

Delay line based Time to digital converter

his is a very primitive TDC and involves a delay-line which is used to delay the reference signal. The other signal is used to sample the state of delay chain. Each stage of delay chain outputs to a flip-flop or a latch which is clocked by the sample signal. Thus, the output of the TDC forms a...

vlsiuniverse.blogspot.com

danadak · Nov 9, 2023

1) A digital delay (counter) needs a clock and some timing function to sync.
It has / adds jitter to the timing event. Commonly used to wait for data to
settle at some input, like a flip flop, before attempting to clock it in. Its the
whole issue of metastability -

Loading…

www.ti.com

Loading…

www.onsemi.com

Loading…

www.ti.com

Loading…

www.ti.com

A non amplified analog delay line is just passive RLC, jitter is reduced to dealing
with just thermal noise of R's and any other noise generating phenomena, like
vibration effects on LC components. An analog delay line is a distortionless
construct that propagates analog signals.

Regards, Dana.

AnalogKid · Nov 10, 2023

Isn't this just an interval counter? Or a shift register? The delay line approach is conceptually more simple, but the precision will be low. What time resolution does the output have to represent?

Also, this seems like a pretty simple task for a masters project.

ak

Harald Kapp · Nov 10, 2023

Lizwi said:
My project is titled "Time to Digital Converter"

Isn't that a clock?

Help us understand your problem by describing it in more detail. A delay line per se is not a time to digital converter. As the name says it simply delays an input signal such that it appears at the output some time later. This can be done in a variety of ways, analog digital, acoustically and even electromechanically.

Delta Prime · Nov 10, 2023

danadak said:
1) A digital delay (counter) needs a clock and some timing function to sync.
It has / adds jitter to the timing event.

Hilemn said:
1) A digital delay (counter) needs a clock and some timing function to sync.
It has / adds jitter to the timing event.

Welcome to Maker Pro!

Here's a little snippet from the link below.
The first time-to-digital converters were developed for scientific and research purposes. They were considered a combination of a time-to-analog (TAC) and analog-to-digital (ADC) converter.