Camera IC ...

On Sun, 16 Sep 2007 01:52:07 GMT, "Arfa Daily" put finger to keyboard and composed:

All I can find are references to VGT7616-nnnn in a 44PLCC package with date codes around 1988. Usbid.com says it is a Vitelic part, but other sites suggest it was made by VLSI Technology. My cross reference book lists VGC prefixes (but no VGT parts) for VLSI Tech, so I would lean toward the latter. I suspect the part is a field or mask programmable ASIC of some kind, as that was VLSI Tech's forte. The variable suffix would tend to support this.

- Franc Zabkar

Hi Franc

That was my first thought as well, as soon as I saw the dash number on it, but I was encouraged when I found plenty of references to it on the net, as well as others from the same series but with different dash numbers. I figured that maybe rather than it being an OEM-specific programmed device, that perhaps it was just programmed up to be a 'useful' chip. It seems to do most of the timing for the CCD readout process, as well as V & H sync generation.

I reckon 1988 would be about right. What I am trying to do with this camera, is to replace a vidicon camera in a system, whose timebases are derived directly from pulses supplied by an external part of the system. If I can figure which pins are ins and which are outs, I may be able to synchronise the VGT chip to the external system. There are plenty of pins which have H rate and V rate pulses on them, so I think that it's potentially promising. Thanks for your interest anyway.

Arfa

If you can find the reference frequency source for the chip (probably a crystal oscillator I would expect) then you could add some varactors (or swap it for a VCXO module) and make it tunable and then use a PLL chip like a 9046 to compare the VSync pulses from the camera with your external Vsync signal, that should get allow you to get the vertical sync to match. Unfortunately I think that will not necessarily get the HSync to match because I seem to remember that there is some difference between the even and odd fields, and I guess that the camera could be doing even fields when the external sync is doing odd fields. I suspect that it might be better to get a camera module with the requisite inputs already fitted, especially if you are not doing this for fun but expect your hours to be paid for in a monetary sense. If you feel like posting a photo, I'd be interested in looking at it, but only if is is no trouble because I'll be no help to you.

Chris