The one problem I have with RGB -> S-Video converters are;
They are bloody expensive.
$100 or more (usuall MUCH more.)
I have a schematic for a Sony CXA1645 RGBS to S-Video/composite converter, but!
I can't find a single source for Sony CXA1645 chips in North America (so far).
I don't think the whole thing would cost more than $45, including connectors and other fiddly bits (which are easily found).
Does anyone have some of these chips, or know where to get them?
any help would be much appreciated. B)
if it helps at all, the md1 has a CXA-1145 encoder in it...
The 1645 should be in any Saturn or Playstation. If you can get ahold of one of these then open it up and go to town. If you feel bad about killing the unit try and find a used or broken one. Chances will be good that the chip is still functional and you might even be able to score the console for free.
oh, youre going to hate me now.. having read the previous post, i am now holding a spare CXA1645M in my right hand as i am typing this:) i can confirm, they ARE on the psx motherboards.. theyre on the underside (or mine was) right by the av port. (too bad for you im in australia;))
Is it a DIP part? (pins that go thru the MB)
Also exactly what model of Playstation,
Old and grey one or small and white one?
They're almost certainly going to be surface-mount, so get your fine soldering skills ready.
it's surface mount, and generally when someone says psx they mean the old grey ones, though some people are a bit clueless.. mine was from one of those.
Any reason why people are not considering using the AD725 instead? (product page here (http://www.analog.com/en/prod/0,2877,AD725,00.html))
No, I've not used the part, but it appears to do the job that's required without needed to sacrifice a whole bunch of electronics to get a single RGB to NTSC/PAL encoder.
The AD275 is a very capable part, but Sony gets the love 'cause it's REALLY common. But then, why not use the impossible-to-find-but-I've-got-one-so-nyah! Sony CXA2075, an upgraded and awesomer pin-compatible version of the 1645.
Lawrence, where'd you get the CXA2075? and what kind of stuff can it be found in? (if any)
QuoteAny reason why people are not considering using the AD725 instead? (product page here (http://www.analog.com/en/prod/0,2877,AD725,00.html))
Well we got into the CXA1645 here first in order to amplify RGB. It's just that it also does S-video so nicely that it's cool to get both in the same package, this is really nifty for Turbo units.
Broken Playstation < Turbo/PC Engine with S-video
Any additional info on the 2075 is most welcome.
My CXA2075 came from a Micomsoft XAV-2s. A google search turns up the best page first, from the designer of the chip (http://www.videoi.com/~pietro/cxa2075/) himself.
PDP-13 Now that we've found you the chip, do you want to share that schematic?
Do we need one? The ex-designer says it is pin-compatible with the 1645.
well, seeing as i dont know how to wire that one either, yes.
i want to use my amiga on my tv, cos i dont have an scart monitor, and tv's here dont really have scart..
i have found the datasheet on the chip though, and i think thatll help.. but if one of you has a better/easyer setup, ill be happy to hear it.
edit:
Endymion, i meant for the 1645..
Oh do please try Google next time, phreak97. You might have found it in a dozen places, like a little site we all like to call gamesx.com (http://www.gamesx.com/rgbadd/cxa1645.pdf).
QuoteAny reason why people are not considering using the AD725 instead? (product page here (http://www.analog.com/en/prod/0,2877,AD725,00.html))
No, I've not used the part, but it appears to do the job that's required without needed to sacrifice a whole bunch of electronics to get a single RGB to NTSC/PAL encoder.
Because the AD725 is not as compatible as the CXA1645. The AD chips don't play well with many video signals I've found from building superguns with both that part and the 1645/2075.
I had a couple of topics in great depth here about 1.5 years ago on building this circuit. In fact I just built 5 last night for Turbo systems. Matt Ross was a big contributer to that discussion and it's worth finding.
Sorry, forgot about actually POSTING the scematic:
http://www.nexusuk.org/projects/rgb2svid/p...s/hpim1066/view (http://www.nexusuk.org/projects/rgb2svid/photos/hpim1066/view)
Thats actually the PAL version; you need to change the parts he talked about to the NSTC ones.
Also I'm thinking... The Sony Playstation has a CXA1675 working happily already...
why do I need to excise that chip from a pre-built circuit?
It works fine already and Playstation S-Video cables can't be too hard to find.
Why not just cut a few solder paths, add a Multi-pole switch
(a 4-pole double throw switch w/two permament positions, 12 connectors), and hack on a few BNC connectors on the outside of the PS...
lazy yes, easier to do than build a whole new circuit with awful surface mount stuff.
and no dead PS1, not that I'm a fan of sony consoles.
could that work?
QuoteWhy not just cut a few solder paths, add a Multi-pole switch
(a 4-pole double throw switch w/two permament positions, 12 connectors), and hack on a few BNC connectors on the outside of the PS...
The concept is sound, there's no reason at all you can use the existing framework and just feed your RGB+S signals to the PS' chip. The downside of course is that the PS isn't exactly a pocket sized adaptor. =)
I've cut the 1645 from the PSX and Saturn boards, leaving as much of the supporting components as possible. I'll be hopefully posting this as a working encoder in the not too distant future.
Also RGB + S need to be grounded right?
Is it OK to use the same common ground?
yes, you can use a common ground
sounds cool hopefully this is what ive been searching for
can someone make a pcb based on the common size of all these parts?
Uhm... Huston we have a problem...
I've got a Sony SCPH-9001 model grey Playstation, and I can't locate the RGB encoder chip on the motherboard...
my question is this; DOES a SCPH-9001 model even HAVE a RGB encoder as a seperate chip :o
I fear that the RGB encoder has been integrated into one of the other chips... making alterations to the device rather impossible.
QuoteUhm... Huston we have a problem...
I've got a Sony SCPH-9001 model grey Playstation, and I can't locate the RGB encoder chip on the motherboard...
my question is this; DOES a SCPH-9001 model even HAVE a RGB encoder as a seperate chip :o
I fear that the RGB encoder has been integrated into one of the other chips... making alterations to the device rather impossible.
i was looking threw my collection of old boards
its only on the first version taht has 3 rca jacks and a micro phone jack.
early version
the chip was removed into the compnet cable or other cable for psx ... guessing
since the other psx'es dont have these connectors
My question is: where are the RGB/synch pins / inputs on the SCPH9001 board?
(what chip handles video?)
It does not matter as long as I can find something to feed my RGB signal into.
(that has good S-Video output)
or am I completely Hosed? :unsure:
To answer my own question:
the A2106R chip seems to do the video...
unfortunately I haven't found a datasheet ANYWHERE, even the all mighty google has failed.
does this part have an alternate name by any chance? like CXA2106, or is it really some slightly updated IC that is compatible with annother one?
also its a quad flat pack.... goint to be very tricky to solder around that, in fact its fiendishly difficult... :ph34r:
seems to generate pretty good quality video though.
i use to mod chip psx back in the day and bought alot of "bad" psx off ebay and repair them so i had a few donor boards.
guess ill have to figure out how to make a board layout
i got the chip from a later psx with no rca jacks. are you sure you checked BOTH sides of the motherboard? mine was underneath it.
werejag: no playstation cable has a chip in it.
Yeah, first thing I did after not locating the CXA1654/2075.
there were NO chips/capacitors/resistors/anything on the other side of the board.
its a october 1999 model PS.
this one also has no RCA jacks or parrallel port. lame.
and the chip I think is video is one of those tiny quad chips with microscopic pins.
(and may even be a custom sony part with no datasheet for the general public)
PDP-11,
To work out which chip is responsible for video encoding just trace the RGB signals from the A/V connector. The video normaly goes from a an IC's output, through a 75 ohm chip resistor to the A/V out.
If it turns out to be something esoteric then go to analog devices' website and order a free sample of an AD724/AD725 video encoder chip. I ordered a few AD725 samples last year without any trouble (still haven't got around to using them though).
Quotei got the chip from a later psx with no rca jacks. are you sure you checked BOTH sides of the motherboard? mine was underneath it.
werejag: no playstation cable has a chip in it.
several of the psx cables had big boxes is what im saying maybe it has the ic in there after the late models did away with the chip
QuotePDP-11,
... just trace the RGB signals from the A/V connector. ...
yes, but where is the Synch
input on the CXA2106R part?
(and for that matter RGB inputs as well)
I don't want the output of this chip but to use it as an RGB -> S-Video encoder.
therefore I need to find the RGB and Synch inputs for the chip.
(and use the Sonys S-Video output as normal.)
and to werejag, I doubt ANY A/V cables have a IC of any kind in them.
It would be needless to include such a part externally from the motherboard.
werejag: those boxes contain only a ferrite tube to act as a noise filter. nothing more.
QuoteI doubt ANY A/V cables have a IC of any kind in them.
No Sony cable has any kind of IC inside, but the GameCube certainly did. The component cables include a digital->analogue chip.
QuoteQuoteI doubt ANY A/V cables have a IC of any kind in them.
No Sony cable has any kind of IC inside, but the GameCube certainly did. The component cables include a digital->analogue chip.
the rf ones had a box not a filter and ive not seen rgb cables for psx
Quotethe rf ones had a box not a filter and ive not seen rgb cables for psx
In spite of your complete lack of punctuation and capitalization, you are completely correct. RF adaptors have RF modulators in the cable. No PS RGB cable I've seen has anything inside the connectors but some capacitors.
If you search around here you will find the models of PSX that had the CXA1645 chip:
1001
5001
5501
If memory serves correctly.
And Lawrence there was that cable made by Lik-Sang or someone that had a 1645 in it for the PSX. Not Sony brand, but existed.
Thanks for the info :)
Whats the video quality like on the Analog devices 725/724 ?
At their side they list it as a very 'economical' component, which is synonymous in my mind with cheap and junky.
Or is it good?
Also a circuit diagram would be nice.
(NTSC, Composite synch, with no luma tap as I'm using Svideo...)
PDP-13,
Download the datasheet and see the app. circuit "Interfacing the AD72x to the (Interlaced) VGA Port of a PC".
The AD725 requires an oscillator (also in the datasheet) and you can leave off the Y-trap componets if you like. If you're using an AD724 you can connect it straight to a crystal without the needs for ans osc. circuit.
I've not personaly seen the output of one of these chips so I can't comment on the quality (i'd expect it to be pretty good though).
The AD chips are different and I don't just mean the look and layout. They perform significantly differently than the Sony CXA chips. I use an encoder that has the AD724 and another that has the AD725 and they don't work with a lot of systems that the CXA does. It really depends what you need it for. The AD chips work great with Neo Geo, Atomiswave, and a few others. They do work with Turbo Grafx and Genesis, but some effort is needed to get them to work.
Really... Hmmm.
well I've given up on the Sony chip... its costly and uncommon.
How tricky can it be?
If I've got a 15Khz RGB and Composite synch input of any sort (in the proper .7 volt range) this chip should be able to handle it right?
(Genesis[32X/CD] / Neo Geo / TGFX-16 / Ect...)
give or take a few capacitors or resistors. Also you can't beat the price. (Free!?! :lol: )
i could sell you a CXA1645M out of a correct model psx which went to parts long ago if you wanted. even though it's international shipping it should be cheap.
"The one problem I have with RGB -> S-Video converters are;
They are bloody expensive.
$100 or more (usuall MUCH more.)
I have a schematic for a Sony CXA1645 RGBS to S-Video/composite converter, but!
I can't find a single source for Sony CXA1645 chips in North America (so far).
I don't think the whole thing would cost more than $45, including connectors and other fiddly bits (which are easily found).
Does anyone have some of these chips, or know where to get them?
any help would be much appreciated."
Maybe you might want to take a gander at this:
http://www.neobitz.com/Pages/Mods/SystemMods.aspx (http://www.neobitz.com/Pages/Mods/SystemMods.aspx)
I don't know the price but it should be inexpensive plus you get Component Video as a bonus. It might also work with Progressive Scan RGB (VGA) - think DreamCast. Imagine playing "Soul Caliber" on a large Progressive Scan capable Component Video TV.
Still can't find one? What about a Sega Saturn? Don't all Saturns have the 1645? Find a broken one and go to town. Some guy on ebay was selling bundles of them last year--yeah, broken!
well, i'd send anyone a cxa1645 for like $10 inc postage... i have only one though
To RARusk; yeah its $100+ US. (no single boards sell for less than $100 and I suspect they use the SAME chip I am.)
To Endymion; sacrifice a PS I might, a Saturn NEVER! (well perhaps a broken one)
Also even if the Analog Devices AD 725 I have sucks hugely, it did not cost me. :P
Too bad those Tiny little pins are going to be uber tricky to solder...
(I'm going to hand solder a thin copper wire to each pin, and that wire will go to a wire wrap board of some kind.)
not a ideal solution but it should work.
If I had a digital camera I would take some pics and make a little guide for those who want to build the same... oh well.
dont use bare copper wire, it oxidizes, itll turn into a resistor eventually. use wire wrapping wire, the stuff i got is some mix of copper and some other coating, itll never oxidize, it's made to be exposed. i soldered bits of it to each pin on a smaller chip with the same pin spacing, then put the wires through a bit of perf board with enough space to not short anywhere. it works perfect.
if you want a pic, let me know, you can all see my crappy job of soldering this one.
can someone make a pcb layout for AD 725 for a neogeo
For any of you wondering how to solder the SOP CXA1645M IC onto a breadboard of any sort, check this little piece of board out.
My RGB -> NTSC converter pics (http://ruliweb.dreamwiz.com/ruliboard/read.htm?main=cmu&table=guild_neo&page=2&num=4843&find=&ftext=&left=i&time=)
That little piece of board will let you mount a SOP IC and then attach onto regular DIY boards' holes.
I took apart a broken Saturn, and snatched a CXA1645M and 2 VHC04 IC's. I used VHC04 in my circuit instead of HCT04 or HC04, because it's just plain BETTER in every aspect, plus 2 of them were in the Saturn for free.
I found it pretty easily, but I'm in korea. You should try to look for these to mount the CXA1645M as well as the subcarrier generator IC (Hex inverter, ie. VHC04), it's no sweat and neat as well.
I wish I knew that I could post as a guest a little sooner.
can you go into more detail so i can build one?
im ntsc since im in the states
Where did that SOIC adaptor come from... that would be much better than soldering transformer core wire to each pin. (and getting half the connections either shorted or cold-jointed... :o )
Also get these PDFs from the Analog Devices site:
120333814AD725eb.pdf
774020909AD725_0.pdf
The evaluation board gives out the whole circuit, but the documents are not that easy to read... <_<
if youre going to solder wires, like i did, dont use transformer core.. it's insulated, and you cant strip it easily.. it's a bitch to work with. use 'wire wrapping wire' and strip the insulation off the whole strand if you need to. it's plenty thin enough for the rgb encoders, and it has an alloy coating so it wont corrode. while yes, it isnt designe for soldering, it solders 100% fine, it's what people use in ps2 mods alot of the time. it's perfect for almost any console mod, it's single strand, no stray bits, it's made so when you bend it into place, it stays there, it's uber thin, and itll take an amp through it quite happily (my tests show it starts getting warm about 1.6A at around 12v or something, it burned the insulation at over 2A). this all means it's perfectly fine for led mods, region switches, anything really. also the insulation doesnt shrink back more than half a mm or so, so it's great for tiny joints where you only want a fraction of a mm stripped off the end.
heres a pic:
wire (http://www.phreak97.experienced.tk/phreak97/smallwire.jpg)
yup...wire wrapping wire is the stuff to use. It's only rated for about 300mA so don't use it when real current is involved.
anyone good at making pcbs
can someone design a pcb for either the ad725 or the CXA1645 chips
The CXA2075 is a great IC, but when in use it gets HOT! There is a CXA2075 in the TV de Advance. The video quality is excellent, but noisy in the TV de Advance because it's a cheap device made in China.
I plan on using either the AD725 or the CXA2075 with my project that includes an ADV7125 video DAC. Probably the AD725 will work best with the AD DAC and produce nice video, but I'm not even sure yet. I'm building a circuit that takes the LCD signals from the DS and converts them into NTSC signals. This is hard enough as it is without worring about what RGB encoder to use.
I have an AD725 Evaluation board. Unfortunately this device (as an eval board) is not compatible with many arcade PCBs. The Capcom CPS1 and 2 based games look awesome... provided that you have about 300 ohms series resistence on R, G, B video signals (to drop the voltage). I haven't tried my Neo-Geo MVS... partially because the free board I picked up doesn't boot properly!
One thing to note about the AD725 is that it can accept both separate and composite syncs.
A fair warning to all you PSX vandals: I gutted SCPH-7501 for spares (needed laser unit for blude debug anyway). Unfortunately there is no CXA1645 chip in this model.