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Help identifying a blown IC and resistor

Hi Folks

I have a COMMAX DRC-4L Video doorphone camera that isn't working anymore.

This is part of a faulty Commax CDV-43k/DRC-4L (Stock Code: PI-1176) intercom that I basically got for free. I think something must have shorted or gone wrong as the power supply board of the main intercom unit (CDV-43k) itself (converting wall power of 220v to 15v) was blown. I've been able to replace the power supply board and had to replace some components (mainly a few ferrite beads and a resistor or 2, if I remember correctly) on the main PC board of the intercom unit itself as well. After that it seemed that the intercom was working and I connected the DRC-4L camera unit, which seemed to power on and the LEDs came on as well, but the camera feed didn't display on the intercom screen. After confirming that everything seems to be correct on the intercom unit, I suspected the camera itself to perhaps also have an issue or perhaps even some blow components.

Long story short, once I remove the camera unit completely, I noticed 2 blown components on the back. An surface mount 6-pin IC (marked U8) and a SMD resistor (marked R23). Here is a link to some photos:

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From what I can make out from the remain bits of the code on the resistor, it seems like the code could be 75R0, which means it's a 75 ohm 0805 SMD resistor, right? Please let me know if I at least got that right.

The IC however, I have no idea what it could be. I'm also not sure of the exact orientation of the chip, in other words where pin 1 is located, but I have indicated on the image which pin I suspect is pin 1. Based on my suspected pin 1, I can tell you that pin 2 is most likely the ground pin, as that is the only pin that has a direct connection (short) with ground. I was also able to detect 12V on pin 3 & 4 when the camera was powered on. Something else that I noticed was that there is a similar looking 6-pin IC, marked U9, towards the right-bottom corner of the board (as indicated on photo:

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The code on that IC is AJ6LE. I checked the same pins and it seems that pin 2 is also ground and I also detected 12V on pin 3 & 4.

I am unable to find any information on the AJ6LE IC online, so I don't know if anyone here could maybe help to find out what exactly that IC is, so that we could hopefully determine if it is likely the same as the IC that has blown.

Otherwise I have also tried searching online for information on the camera board itself, but couldn't find anything that gave me any indication of the specs of the IC or what IC to try and replace it with. I also tried to search for the schematic, but couldn't find anything.

Also the leads coming into the camera board is: - Red is 12V+ - Blue is GND - Yellow is Video

Here is a link with a few photos of a circuit board that isn't working anymore:

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If anyone can perhaps help me identify the blown IC or perhaps point me in the right direction that would be greatly appreciated.

Let me know if you require any other information from me.

Regards, Jannie

Reply to
Jannie Brand
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That appears to be a current device - or at least it is available on the open market. Have you tried the "mother ship", being the manufacturer?

Here, also, is a current source:

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Peter Wieck Melrose Park, PA

Reply to
Peter W.

Those six pin ICs are trouble. Some of them are only switches, and you can work around them assuming you know exactly what you're dealing with. Somewhere in a box I have a very expensive portable HDMI generator with that type of chip that failed and burned the numbers off it. I don't really need it anymore, but it would be nice to have anyway.

Reply to
ohg...

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looks like the design is seven years old. Good luck getting information from the OEM.

Reply to
Michael Terrell

Yes the resistor value is correct. Here is a webpage that can help

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Any chance you can locate a similar unit and take a peek inside? J

Reply to
three_jeeps

Hi Peter,

I have actually sent an email to the local distributor here in South Africa (Spectrum Security Products) to hear if they maybe have any replacement parts available for this camera unit. I assume that if they do, then it might cost a pretty penny as the camera unit itself is not cheap around here, but who knows, maybe I get lucky. It would obviously be much cheaper to just fix the current board, if at all possible.

Regards, Jannie

Reply to
Jannie Brand

Hi there,

Yeah, I was thinking the same thing, but the units are a bit expensive to buy just for that and then I'll be stuck with a 2nd unit that I wouldn't need. Also, even though I considered it, I wouldn't want to buy a unit, open it up just to peek and then put it back together again and return it ... just doesn't feel like the right thing to do.

I'm also on the lookout locally for 2nd hand units, but it seems that people rarely sell the camera unit on it's own, it's usually the full intercom system. I might still get lucky, but time will tell.

Regards, Jannie

Reply to
Jannie Brand

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