Anyone familiar with the EL9115 Triple Analog Video Delay IC?

Found it when I was looking for information on older profanity delays designed for analog video (without much luck) since having a variable delay that could accept composite or RGB would be really handy.

These top out at about 50 nanoseconds so they aren’t useful for that, but I have a feeling they could be handy for other stuff. No example circuits in the datasheet, though.


Might be similar to Bastien’s CBV002 delay module?
What you want might be Video Delay – Now in Colour. | Synkie

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@TubularCorporation delays produced by EL9115 sounds a bit small: looks like its typical application is compensating for delays induced by long CAT-5 cables. Though the 3 delays inside the chip can probably be chained to achieve longer delays (and even more with multiple chips). Then, chroma subcarrier frequency have a period of around 220/280ns depending on the standard, so chaining the delays inside EL9115 (180ns) would give for a bit more than 180° hue shift on composite video signals.

@VisibleSignals CBV002 uses TDA4565, which has around 1000ns/1us max delay, and a line of video in composite is 63.5/64us, so it results in a small horizontal displacement, combined with “hue shift” as the chroma subcarrier is also delayed with luma.

As for audio, analog delays made out of passive components can’t “hold” the signal for very long, and also introduce some loss/noise to the signal. Else, there is not many other ways than going digital as the Synkie does (ADC, FPGA, RAM, DAC), though not especially easy to implement, so that’s also a good reason to “misuse” analog delay chips :slight_smile:

Interesting thread about video delays Video Delay Lines


Yeah, 50NS is very short and to get a longer delay you pretty much need a framebuffer, that’s just how I happened to stumble on these not what I think they’d be useful for (but thanks’ for the link to the CVB002, that’s definitely something I might try to build later in the year when I can afford it).

I was thinking more along the lines of multiple ICs in parallel to microtime the RGB channels independently, or putting the delay in a feedback loop. I’ve looked at the actual commercial devices that are meant for compensating for cable latency, but all I can ever find are digital and very expensive (the cheapest delay I know of is still a few hundred dollars, and it’s SDI so it’s completely useless for me). Signal degradation is a feature not a bug for me.

I’m far from being able to design something around this myself, though.

EDIT: that delay line thread is good, I missed it so thanks for pointing it out too.

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