| lasso |
Hi,
Long time reader, first time poster.
Like so many others here, I've put together a TDA1543 DAC to venture into the DIY DAC world. For starters, I've intended to keep the circuit roughly according to the datasheets of the respective components.
But the problem I have now is that the DAC sounds good only at low volume and distorts badly when the samples reach a certain level. (Tested with a SlimDevices SqueezeBox, which has a digital volume control.)
See eg http://my.opera.com/lasso/homes/alb...1osc440Hz_1.png . Links to more pictures below.
More details:
The main components:
* TORX173 optical jack (TTL out)
* CS8414 receiver
* TDA1543
* 7805 regulators
The CS8414 is surface mounted on an adapter.
I started with only one regulator for all components. (While searching for errors I added a separate 7805 for the TDA1543, but to no avail.)
Missing from the schematics are 100 nF on each of the V+/V- pairs on the CS8414.
At first I thought that I might have fried the CS8414 or that the TDA1543 might have been defect, but I've tried exchanging them and I still get exactly the same behaviour.
I've also tried adding more capacitance to V+ and V- of the TDA1543, but it didn't change anything.
Schematics, images of the prototype board and screenshots of the recordings are here:
http://my.opera.com/lasso/albums/show.dml?id=45429 .
Could the oscillation-like spikes be caused by digital switching? If so, how easiest to remedy that?
I'm aware that digital circuits should be given special care, but I also would like to keep the circuit as simple as possible while breadboarding. Hence no abundance of regulators, ferrite beads and so on.
But apparently the circuit is a little too simplistic and/or plain wrong. :-) Either in the design, or that the layout is done in such a way so that this problem is caused.
Does anyone have any ideas or suggestions? Do I need to provide more information, and if so, what?
Any help would be truly appreciated! |
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| EC8010 |
The traditional waveform for testing a DAC is a ramp. Nevertheless, your picture shows that the initial problem is something to do with the MSB as the waveform changes polarity from + to -. After that, for some reason, the next most significant bit seem to get its knickers in a twist (technical term). The 1543 is a current DAC and it looks as though it's not seeing a proper load. I'd be looking very hard at soldered joints into the I to V convertor.
A photograph is always helpful. |
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| rfbrw |
| I notice the dac chip seems to have been painted over. Are you sure it is a TDA1543 and not a TDA1543A or a TDA1545A, as at first glance everything else seems okay. |
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| scottnixon |
| Mode is set wrong. Need to do something with pins 13 and 16 |
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| lasso |
Thank you for all your comments. I follow up below.
| quote: | | EC8010: The traditional waveform for testing a DAC is a ramp. Nevertheless, your picture shows that the initial problem is something to do with the MSB as the waveform changes polarity from + to -. After that, for some reason, the next most significant bit seem to get its knickers in a twist (technical term). The 1543 is a current DAC and it looks as though it's not seeing a proper load. I'd be looking very hard at soldered joints into the I to V convertor. |
Waveform: I've taken some new measurements using a 440 Hz sawtooth (dunno if that would be the traditional form, but audacity could generate it :). The result was pretty interesting, the DAC doesn't seem to be outputting anything negative:
http://my.opera.com/lasso/homes/alb...440_tda1543.png
Just to make sure that my measurements weren't totally off, I also took the output straight from the SqueezeBox DAC. It shows a little ripple at the extremes, but is otherwise ok:
http://my.opera.com/lasso/homes/alb..._squeezebox.png
About joints: I've doublechecked all the joints and reheated all of them. All of them seem to be good, but still the same results. (Or did I misunderstand you?)
| quote: | | rfbrw: I notice the dac chip seems to have been painted over. Are you sure it is a TDA1543 and not a TDA1543A or a TDA1545A, as at first glance everything else seems okay. |
I think this is because of the angle in the photo. The text is pretty clear from other angles. In real life the chips only have a kind of strange structure in the plastic, but it's not paint. I checked the whole tube of chips I have yesterday, and they look non-fake, at least to me.
But the thought that I had got TDA1543A has struck me... But then I'd assume that they wouldn't even work for low volumes, since the input format is totally different?
| quote: | | scottnixon: Mode is set wrong. Need to do something with pins 13 and 16 |
The way I read the CS8414 datasheet, pins 13 and 16 seemed unrelated to mode selection. They only seem to control the status output on pins 2-6 and 27. Did you mean other pin numbers or have I read completely wrong?
I just did a quick test, setting pin 13 low and pin 16 high, which would indicate that I want to see only channel information and won't have a clock connected to pin 13. Same result as earlier. |
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| EC8010 |
| The 440Hz sawtooth waveform shown in your second graphic is a good test waveform. Assuming that the settings on your "oscilloscope" (soundcard?) are the same, the first graphic is a disaster. There's something seriously wrong and the DAC doesn't appear to be reading the data correctly at all. |
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| lasso |
Yep, the settings are the same, and yep, I'm using my soundcard for looking at the signal. It isn't too bad for superficially looking at an audio signal, but of course I stand no chance of analysing eg the digital data that goes into the dac. Maybe I'll get an oscilloscope one day... :)
I've now redone the whole I/V stage in a new position on the protoboard, and triplechecked all the connections on the CS8414 with the datasheet and my schematics. No difference schematics-wise, but still the same (bad) result.
I did an image search for TDA1543, and most of them have a printed line on them between pin 1 and 8, approximately. Eg:
http://www.kyohritsu.com/CATALOG/SE...OTO/tda1543.jpg .
However, my chips lack the line:
http://my.opera.com/lasso/homes/alb...9/tda1543_1.jpg
http://my.opera.com/lasso/homes/alb...9/tda1543_2.jpg
Can't say if it means anything. I'll try to get hold of a TDA1543 from another source to try with. (I already have CS8414 from two different sources, and they both act the same.) |
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| Elso Kwak |
| The TDA1543s look strange to me... Too lazy to check the schematic........:bigeyes: |
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| ash_dac |
| quote: | Originally posted by Elso Kwak
The TDA1543s look strange to me... Too lazy to check the schematic........:bigeyes: |
They look like someone has been at them with sandpaper (see top right tda1543 for example).
Where did you source them from ?
(maybe sourced from old cd players, and damaged during removal ) |
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| guytou |
..."But the thought that I had got TDA1543A has struck me... But then I'd assume that they wouldn't even work for low volumes, since the input format is totally different"
when you feed a 16 bit DAC with a 18 bits stream ,,you get the same behaviour your DAC present . |
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| rfbrw |
| quote: | Originally posted by guytou
..."But the thought that I had got TDA1543A has struck me... But then I'd assume that they wouldn't even work for low volumes, since the input format is totally different"
when you feed a 16 bit DAC with a 18 bits stream ,,you get the same behaviour your DAC present . |
Not necessarily. It depends on the justification of the data. If, for example, you feed the TDA1543 with I2S formatted data greater than 16 bits, it simply ignores anything over 16 bits. If, OTOH, you were to send 18bit LSB or right justified to the TDA1545A, the MSB would be 2 bits out of position. In effect, bit 16 of the 18 bit word would be treated as the MSB. A sign of this effect is heavily clipped audio.
The TDA1543A is most inflexible. SCLK is fixed at 48Fs. Any other rate usually leads to noise. |
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| BL21DE3 |
Just wanted to say I have sixteen TDA1543's that look identical and have the same batch/serial no.s as the ones that Lasso posted images of. I sourced these as new in the UK from a supplier used/recommended by members of another forum. I haven't been able to test them as my NOS DAC is still in the construction stage. However I'm now getting concerned for the autheticity of my chips :( . If anyone can confirm that these are genuine TDA1543's I'm sure both myself and Lasso would be grateful.
Regards,
Ewan |
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| jean-paul |
| FWIW I have never seen original Philips TDA1543 with sandpaper surface and printed like that. |
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| rfbrw |
| If you have a device with a CXD2500 in it, a quick test to see if they are TDA1543A's is possible. |
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| jean-paul |
| That's what I was thinking too. |
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| Elso Kwak |
Genuine?
:confused:
:clown: |
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| Elso Kwak |
The ones from Thailand sound a shade more bright....
:cool: |
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| rfbrw |
| quote: | Originally posted by Elso Kwak
The ones from Thailand sound a shade more bright....
:cool: |
Must be the sunny disposition of the workers at the fab.
Hi ho hi ho its off to work we go........:happy2: |
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| lasso |
| quote: | | ash_dac: Where did you source them from ? |
I got them from a shop in the UK. They had really good service, and I don't distrust them.
So I choose to assume that I'm to blame until I have made the DAC work (possibly with a chip from another source).
Seeing Elso's pictures, there truly seems to be a wide range of print designs on those chips...
The "Philips" text (or supposedly so) printed on my chips is much much blurrier than on any of Elso's, though. But that could also mean nothing more than that the print is exactly that -- blurrier. :) |
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| JohanH |
Hello Lasso,
I had the same problem. As I couldnīt solve it quickly enough I gave up on this DAC. As far as I could gather it is, as was mentioned before in this thread, a load problem. Playing with variable resistors on Rload and Rref I could improve the sound but didnīt get it right in the end.
I even ripped a TDA1543 from a Philips CDP to compare to the ones I used, but same result.
Anyone interested in a stuffed DDDAC board with several TDA1543s?
In the end I think with patience I could have gotten it to work properly; unfortunately not my forté.
Cheers and good luck,
Johan |
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| lasso |
Thank you for your input, JohanH. Good to hear from someone else having problems as well, but of course a pity that your DAC didn't work either.
About the I/V stage: I investigated carefully how to calculate the I/V resistors and the bias current, and when I measured them, the currents seemed to be within specs, IIRC.
But if we for a moment would assume that the problem *is* that the DAC sees a strange load, what possible causes could it have?
* wrong resistance
* bad solder joints
are probably the obvious ones. I've checked, doublechecked and triplechecked these.
The resistor values are nothing magical, it's all in the datasheet (when you figure out how to read it :-), and besides, there are many designs on the net to check for what's being used. My values don't deviate much from others', if at all.
My soldering: well, ugly as it may be, it usually gets the job done, and I seldom have cold joints. And as I've mentioned, I resoldered the whole DAC + I/V stage the other night. And doublechecked the new joints. And the result was exactly the same, sound-wise and measurements-wise.
So, what more potential issues could there be?
* wrong capacitor type? (wima metal film caps, nothing fancy)
* bad grounding? (DAC and I/V are all grounded directly to regulator)
* cable lengths, interference, parasitic/stray capacitances? (cables are not overly long, but had I made a PCB the paths would have been shorter)
* the CS8414 is on an adapter (with all soldering triplechecked on two different chips), but could the adapter with the extra leg lengths cause disturbances in itself?
* ... something else?
These are things I considered before starting, but I wanted to wire up the DAC point-to-point to be able to experiment, and I didn't really think any one of these issues would affect the basic function of the thing. And I still don't find it likely, I would tend to think about them to be more of "the last 5-10 %" things.
But what if one or several do matter? In that case, which one is the most likely troublemaker? |
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| lasso |
| quote: | | Check it out everyone else ties pin 13 to ground |
Well, not quite everyone, but I grounded it during the start of my investigations and forgot to update the schematics. Sorry about that. (It didn't make a change.)
| quote: | | (do you have separate analogue, and digital grounds ?) |
Well, not really. But when several chips share the same regulator, would that really matter? I can see how separate groundplanes can help with their relatively large amount of copper, but the short wires?
| quote: | | Pin 16:- well the ddac design has it high, and the other has it low ! Try it high try it low |
According to the datasheet, it only controls what information should be displayed on the info pins. But of course I tried your tip anyway. :-) Unfortunately to no avail.
| quote: | | Also you need to improve the grounding ! |
Any specific tips on what to do? Now, the circuit is pretty much star grounded, where each chip has its own ground cable going directly to the regulator (the CS8414 has two cables, one for digital and one for analogue).
Suggestions to improve that further?
| quote: | | ..and i'm not sure about the 2700pf coupling caps (I use 10uf) |
Oops. Miscalculation. The caps surely formed a high-pass filter with whatever resistance their connected input would have, and most likely with a cutoff frequency in the kHz range. Gah *smacks self*. Switching the caps to higher values (0.33 μF were the largest I had at hand) completely changed things. Thank you for spotting this!
---
Now, even with this change, the distortion remains at approximately the same digital levels as before. However, the big change is that the saw tooth signal actually looks like a sawtoot signal. Well, not really, because it's inverted... :eek:
Another interesting thing that I just noticed is that the channels are actually switched as well. I have the right channel to pin 8 on the TDA1543 as specced in the datasheet, but a sound in the right channel turns up being played in the left channel. My Squeezebox does the right thing. I've attached a screenshot showing both of these things.
I think it's because I was so preoccupied with the distortion that I didn't notice this channel switch earlier.
One thought I had was that there might be some miswiring of the TORX173 optical receiver involved, so I exchanged it with a regular coaxial input instead. But the sound remains the same. And RXN and RXP are correct as per the datasheet, AFAICT.
So now I'm suspecting a protocol error, since in EIAJ, the word clock is inverted compared to I2S. I found this picture in this thread showing the signals side-by-side.
Wouldn't the high volume output + the switched left-right channels be consistent with the CS8414 outputting I2S, and the TDA1543 receiving EIAJ? (I don't think the other way around would give these results, but it's getting late here so I might be a slow thinker.)
Edit: I can't see how it can explain the inversion, though.
I'll hopefully be able to try out switching modes on the CS8414 tomorrow, after checking its current mode config for the umpteenth time of course.
In the meanwhile, any thoughts on this? |
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| ash_dac |
| quote: | Originally posted by lasso
Any specific tips on what to do? Now, the circuit is pretty much star grounded, where each chip has its own ground cable going directly to the regulator (the CS8414 has two cables, one for digital and one for analogue).
Suggestions to improve that further?
---
I think it's because I was so preoccupied with the distortion that I didn't notice this channel switch earlier.
So now I'm suspecting a protocol error, since in EIAJ, the word clock is inverted compared to I2S.
Wouldn't the high volume output + the switched left-right channels be consistent with the CS8414 outputting I2S, and the TDA1543 receiving EIAJ? (I don't think the other way around would give these results, but it's getting late here so I might be a slow thinker.)
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Hi,
Grounding...not specific but check out the tda1543 pcb designs on the forum.
CS8414 outputting I2S, and tda1543 receiveing EIAJ surely that means you have a fake chip ?
I would seriously try and source another tda1543 chip. |
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| rfbrw |
| quote: | Originally posted by ash_dac
CS8414 outputting I2S, and tda1543 receiveing EIAJ surely that means you have a fake chip ?
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It means that between the '8412 and the '1543 lies circuitry of some sort reformatting the data. I would have thought it unlikely that such a thing would be missed. One would be better served looking for a more plausible explanation of events. |
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| lasso |
Well, unless my TDA1543s are really TDA1543As, but marked up wrongly?
(But no, I can't tell how plausible this is, really. It just seems it's something I'll have to look into, unless someone else has any ideas of course.) |
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| rfbrw |
| quote: | Originally posted by lasso
Well, unless my TDA1543s are really TDA1543As, but marked up wrongly?
(But no, I can't tell how plausible this is, really. It just seems it's something I'll have to look into, unless someone else has any ideas of course.) |
Even if they were TDA1543A's, consider the logic of the proposition and rate its plausibility accordingly.
The '8412 has a range of output formats. The '1543A has its particular input format. For the proposition to be remotely plausible, the '8412, in response to a request by the '1543A or through an ability to read chip labels, would somehow have to reformat its out to match a format not included in its range of master mode formats.
Simply put, if the format of the '8412 is set to a particular type, it will not change, irrespective of what the downstream device is. |
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| lasso |
| quote: | Originally posted by rfbrw
Even if they were TDA1543A's, consider the logic of the proposition and rate its plausibility accordingly.
The '8412 has a range of output formats. The '1543A has its particular input format. For the proposition to be remotely plausible, the '8412, in response to a request by the '1543A or through an ability to read chip labels, would somehow have to reformat its out to match a format not included in its range of master mode formats.
Simply put, if the format of the '8412 is set to a particular type, it will not change, irrespective of what the downstream device is. |
Oh, perhaps I wasn't entirely clear last evening. What I meant was that the I2S data from the CS8414, when interpreted as EIAJ, could give at least some of the symptoms that my circuit exhibits (switched channels, low-value digital signals interpreted as larger values etc).
The communication between the CS8414 and the TDA1543 is strictly one-way, I didn't mean anything else than that. |
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| Elso Kwak |
TDA1543 does work with CS8412, TDA1543A does NOT work with CS8412; simple as that!
:cool: |
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| Igla |
Elso;
with what would TDA1543A work?
I have two of them and I would be glad to know how to use them.
Regards;
Igla |
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| rfbrw |
According to the schematic the i/v resistors are 887R each and the reference resistor is 1K
From the above Iref is (Vref/1K)xAIbias = (2.2/1000)x2=4.4mA
This is then added to the output current. The fullscale output current for each output is 2.65mA and added to Ibias yields a total of 7.05mA per output. Full scale output voltage is 7.05mA x 887R = 6.25V. This seems a little. It makes a mockery of the compliance limits of the chip and the V+ rail is only 5volts. Perhaps you should reconsider some of the resistor values. |
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| Carl Ekblom |
| quote: | | Oh, perhaps I wasn't entirely clear last evening. What I meant was that the I2S data from the CS8414, when interpreted as EIAJ, could give at least some of the symptoms that my circuit exhibits (switched channels, low-value digital signals interpreted as larger values etc). |
My TDA1543 dac is perfectly working but switch channels. And it inverts the signal and should do so.
Check that the voltage is close to 2.8VDC (this is important)
at the outputs when no signal is applied. This is valid for +5V supply voltage.
Carl |
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| maxlorenz |
Dear Lasso:
I am the first to confess I don't know what I'm talking about but I have to agree with rfbrw: for me Rref worked when equal to 2/3 to 3/4 of Rload (but my V+ is 8.5V :eek:)
Doede recommend to set 3.85VDC for pins 6-8 for his 8*dac, and VDC at pin7 is around 2.25 if I recall well. I don't know if this helps. :angel:
Also consider chip's Tš as a problem.
Good luck
M |
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| Elso Kwak |
| quote: | Originally posted by Igla
Elso;
with what would TDA1543A work?
I have two of them and I would be glad to know how to use them.
Regards;
Igla |
Hi Igla it works with Sony format. And only that!
:cool: |
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| ash_dac |
Hi,
How did you guys deal with the noise out of your tda1543 NOS dacs? (not scoped mine but connected to computer and NOS noise clearly visible)
I've retired mine for a while as I swear my tweeters cut out the other day!
Might be due to high IV values causing clipping I guess.
Seem to be working fine now though which is a relief.
Speakers:B&W DM570 (with metal dome tweeters) |
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| Igla |
Elso;
I know.
I just can't find any schematic on the net.Do you have some schematic?Could you recomend some easy to get receiver?
Regards;
Igla |
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| Elso Kwak |
| quote: | Originally posted by Igla
Elso;
I know.
I just can't find any schematic on the net.Do you have some schematic?Could you recomend some easy to get receiver?
Regards;
Igla |
No, I tried it in a Sony CDP and saw it also in a Philips full of Japanese chips. |
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| lasso |
| quote: | Originally posted by rfbrw
According to the schematic the i/v resistors are 887R each and the reference resistor is 1K
From the above Iref is (Vref/1K)xAIbias = (2.2/1000)x2=4.4mA
This is then added to the output current. The fullscale output current for each output is 2.65mA and added to Ibias yields a total of 7.05mA per output. Full scale output voltage is 7.05mA x 887R = 6.25V. This seems a little. It makes a mockery of the compliance limits of the chip and the V+ rail is only 5volts. Perhaps you should reconsider some of the resistor values. |
When I was pondering this, I found this interpretation that seems logical: how to calculate the I/V stage .
What values would you recommend instead? As the datasheet is not overly pedagogic, of course there may be misinterpretations floating around (including mine). |
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| rfbrw |
| quote: | Originally posted by lasso
When I was pondering this, I found this interpretation that seems logical: how to calculate the I/V stage .
What values would you recommend instead? As the datasheet is not overly pedagogic, of course there may be misinterpretations floating around (including mine). |
The TDA1543 is supposed to operate into a virtual earth. If you choose to ignore the datasheet a go with this passive iv lark, you can't complain when it all goes wrong. The opamp based iv in the datasheet works but if you insist on passive iv you could try upping Rref from 1k to around 3k9. |
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| lasso |
| quote: | Originally posted by rfbrw
The TDA1543 is supposed to operate into a virtual earth. If you choose to ignore the datasheet a go with this passive iv lark, you can't complain when it all goes wrong. The opamp based iv in the datasheet works but if you insist on passive iv |
:) Nah, not really complaining (at least I hope it doesn't seem like that), and I'm not really insisting on passive I/V either. (In fact, I already have all the parts for the active I/V from the datasheet.)
My reason for passive I/V is because it's what "everyone" seems to be using. But on the other hand, very few seem to power the TDA1543 with only 5V, most use higher voltages and they also stack the chips.
I might try 8V just for the sake of it, using values from some of the schematics off the net, before going for the opamp I/V as you're suggesting.
| quote: | | you could try upping Rref from 1k to around 3k9. |
Should the I/V resistors then stay the same at ~900 Ω?
And, does this mean that the method for calculating the restors in Kuei Yang Wang's post (that I linked to) is incorrect? |
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| lasso |
| quote: | Originally posted by Carl Ekblom
My TDA1543 dac is perfectly working but switch channels. And it inverts the signal and should do so. |
Hm, on closer thought I've seen somewhere that it's supposed to invert the signal, but should it really switch the channels as well? Why haven't Philips just swapped the right and left in the datasheet then? :boggled:
| quote: | Check that the voltage is close to 2.8VDC (this is important)
at the outputs when no signal is applied. This is valid for +5V supply voltage.
|
Aye, noted. I take it that you're running your DAC on 5V? What values are you using for the three output resistors? |
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| rfbrw |
| The final values of Riv at 2k4 and Rref at Ik5 are correct for the scenario he outlines i.e V+ at 8v. |
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| Carl Ekblom |
| quote: | | haven't Philips just swapped the right and left in the datasheet then? |
yes, the datasheet isnīt correct here
| quote: | | Aye, noted. I take it that you're running your DAC on 5V? What values are you using for the three output resistors? |
Iīm running the dac at 8V with 2k output resistors and a adjustable resistor for the current sink. The calculations in the link you submitted is as far as I see it correct. Your schematic is OK.
Carl |
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| Igla |
This calculations for I/V are close.But isn't more easy to connect the scope at the output and adjust Rref, so the DAC won't clip.
I also run TDA1543 on 5V; my I/V resistors are 1k and according to my scope Rref must be between 900ohm and 1100ohm or the DAC clipps.As simple as that.
Am I missing something?
Regards;
Igla |
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| Carl Ekblom |
| quote: | | haven't Philips just swapped the right and left in the datasheet then? |
yes, the datasheet isnīt correct here
| quote: | | Aye, noted. I take it that you're running your DAC on 5V? What values are you using for the three output resistors? |
Iīm running the dac at 8V with 2k output resistors and a adjustable resistor for the current sink. The calculations in the link you submitted is as far as I see it correct. Your schematic is OK.
Carl |
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| rfbrw |
| In the belief that self-flagellation is good for the soul, I just put one of these TDA1543 dacs together. Riv 750R and Rref 1k. Alas, it works. Channels are correct in line with the datasheet and no nasties. Will hit it with 0dB and see what happens. |
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| lasso |
| quote: | Originally posted by rfbrw
In the belief that self-flagellation is good for the soul
|
:)
| quote: | | I just put one of these TDA1543 dacs together. Riv 750R and Rref 1k. Alas, it works. Channels are correct in line with the datasheet and no nasties. Will hit it with 0dB and see what happens. |
This is most interesting. Do you see any major differences vs my schematics?
My datasheet has the right channel on pin 8, is that what yours has as well? Also, is your outsignal inverted or not? |
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| Elso Kwak |
Self-flagellation????
Well, well this forum keeps surprising me!
What's next? Self-humilation?
:clown: |
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| rfbrw |
| quote: | Originally posted by lasso
This is most interesting. Do you see any major differences vs my schematics?
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A CS8412 and minor variations in the TDA1543 resistor values aside, there are no differences.
| quote: |
My datasheet has the right channel on pin 8, is that what yours has as well? Also, is your outsignal inverted or not?
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Right channel is on pin8 and the phase ident signals seem alright. As for the sine wave, can't see how one can tell whether it is inverted or not. Its off a test disc. |
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| Elso Kwak |
| quote: | Originally posted by rfbrw
Right channel is on pin8 and the phase ident signals seem alright. As for the sine wave, can't see how one can tell whether it is inverted or not. Its off a test disc. |
Use a testdisc with a needle signal. Not that I hear any difference; must be my old ears....
:rolleyes: |
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| rfbrw |
| Good idea, I'll try that later. There is only so much of the TDA154x stuff I can take and still remain sane. |
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| Elso Kwak |
Jim Hagerman wrote a paper why NON-OS is bad. Must sound like music to your ears rfbrw!
http://www.hagtech.com/pdf/not16bit.pdf
He cancelled his NON-OS TDA1543 DAC. It had some interesting circuit details though...
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| rfbrw |
| He definitely tried his best to make the pig fly but no deal. After 30 minutes of the TDA1543 this morning, it will probably take another day or two of continuous Lemonjelly and Orbital in the player to recover and I will have to build something else to cancel out the negative karma that came from building the TDA1543 dac. |
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