CurtPalme.com Home Theater Forum

Graham Johnson · Posted: Thu Jan 29, 2009 3:13 am Post subject:

Hmmmm, I pointed out the error of many people wantng a G90 for just this reason approx 2 years ago and got laughed at.

Funny how the worm turns. G90's where never worth the premo price that was being paid for them even 2 years ago.

bbfarmht · Posted: Thu Jan 29, 2009 3:21 am Post subject:

I'm glad I have a Barco!!!!! Mr. Green

Tinman · Posted: Thu Jan 29, 2009 4:17 am Post subject:

Curt, I did a little reading on this. One thing I have discovered on SONY CPU boards is the fact that the SMD aluminum capacitors have gone bad by now. I have re-capped MANY boards with standard caps, bending them over on their sides where space is tight. The leaking caps have a direct effect on the DACS in my case.

I'd be surprised if the G90 CPU is any different.

It's worth a shot if no one has actually looked at those wretched capacitors yet. Nowadays I just pull them all off and replace them.

Analog Marty · Posted: Thu Jan 29, 2009 4:19 am Post subject:

Any chance of copying the chip ? Are there blanks that fit the criteria ?

Tinman · Posted: Thu Jan 29, 2009 5:27 am Post subject:

1031 · Joined: 22 Mar 2006 Posts: 657 Location: Finland

Has anybody looked if Sony has used that chip in another products? or is that chip used only in G90? if that chip has been used in cheap consumer electronics maybe those products can be used as part doner. Ok its not easy job to check that, but sparepart sales can check by component type that if that chips has used in some another products.

km987654 · Posted: Thu Jan 29, 2009 9:17 am Post subject:

Sony has made very good products over the years but they have not learned too much. Their view has been to try to control the market with some proprietary aspect of the product wether it be licensing, hardware or software they tried it with VHS and BETA video products. It does not surprise me that there is some proprietary chip in the G90 (and probably the other sony models) and it would not surprise me if it was made under license by a third party only to be supplied to Sony.

Good Luck Here.

**Curt Palme** · Posted: Thu Jan 29, 2009 1:38 pm Post subject:

I appreciate the input. I wasn't really inferring that we'd chase Sony down via lawyers, I've got no time for that. Smile

Just figured someone might know if the 7 year rule for supplying parts still stands.

AS for the chips, it's a tough call. Considering the chip is 'buried' somewhat in the set, away from HV arcs and power surges, you'd think a chip like that would NEVER fail, so I'm guessing that Sony probably figured the same, and simply made an 'estimated' number of chips that they thought would fail over time.

Having had limited discussions with manufacturers, I understand that this is the way they stock spare parts: Estimate what they think will fail over say that 7 year period of time that they need to stock. Perhaps there's an internal design flaw in the chip that causes it to self destruct, maybe there is some external power surge or overload that is causing the chips to go. Maybe it was a bad run of chips since it appears to be custom made? Who knows, I'm only guessing here.

Hopefully there is a stash out there somewhere, otherwise there will be a LOT of pissed Sony owners.

**Curt Palme** · Posted: Thu Jan 29, 2009 1:40 pm Post subject:

Tom.W · Joined: 09 Mar 2006 Posts: 6635

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

I'm not surprised that the G90 is the only Sony product using these. I've been using Sony products for about 30 years now and I've been into most of them and that was the biggest problem I found was alot of the chips where specific to only that Sony model/product and the only supplier for those specific chips was always Sony only.

It might be worth it to have a subboard built to retro fit in place of this chip. If the chip is only used for the brightness/contrast etc., then it is only ramping a DC voltage up /down via the dac for each function and no doubt this is controlled by a I2C logic stream.

WanMan · Joined: 19 Mar 2006 Posts: 10270

How about asking Moome if a PCB factory in Taiwan can replicate the IC for a batch of 10,000.

Tom.W · Joined: 09 Mar 2006 Posts: 6635

Whats really lousy is they haven't even provided a replacement card with the chips since before June 19 2006 Rolling Eyes

http://www.curtpalme.com/docs/SonyG90_TB30-2006-088.pdf

**AnalogRocks** · Posted: Thu Jan 29, 2009 3:53 pm Post subject:

I remember that Tom. We thought they must be joking....

kschmit2 · Posted: Thu Jan 29, 2009 4:00 pm Post subject:

**AnalogRocks** · Posted: Thu Jan 29, 2009 4:01 pm Post subject:

Yeah, a few spares for the next time they fail Wink

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Nice to see alot of people wanting to try to help. Let me just say I have spent 10's if not 100 hours searching out clues for this chip. I have also spoken with people at Sony only to get finger pointing. Also know that projectors fall under Sony Business and Professional section so looking or complaining anywhere else wont help.

So lets discuss the chip...........

First off the chip is NOT a DAC............it is a DAC controller. It's primary use is to control a DAC and groups of DAC's. It DOES have a data storage section. We also konw that this section is used to temporarily store info during operation.The big problem is without a datasheet we can only assume various functions of the chip. The chip may also require firmware to function but that I cant say for sure. If it does then that creates even another problem.

Here is some info I believe to be correct but I wont say its 100% accurate. CXD305-127R is an 80 pin LQFP. I believe its an 8 channel, 12 group controller.

A datasheet would be very helpful. If it does have firmware (which I'm not convinced it does) it could be hotwired to retrieve as long as the security measures have not been activated.

So as it stands we either need to find chips or the manufacturer of the chip or a datasheet. If all this fails then its the long shot attempt, which is:

Find an 80 pin, LQFP, 8 channel, 12bit X 6, DAC controller capable of 12 group data................ identify correct pin locations............then if all that is met.......find someone willing to pop one in and see if it functions. If there is not any firmware required then it should work. Speed of the chip would not be known but this may not be a mandatory requirement.

More comments are welcome. Challenge my comments...... search for some 80 pin controller's.... maybe we'll get lucky during the search...........

**AnalogRocks** · Posted: Thu Jan 29, 2009 5:00 pm Post subject:

Anyone speak Japaneese? Let's call the engineering team in Japan. ??

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Spanky Ham · Joined: 22 Mar 2006 Posts: 5643 Location: Comedy Central

Wow, I won't pile on and say that you should have bought a Marquee, Barco or even an Ampro. Very Happy

There should be some CRT guys in Japan that could hunt down some of the original designers or at least their documents. I hate to say it, but it may be cheaper to hire tse to redesign the G90. Smile