TDA1541 info

[Pedja]

Henk, thanks for the input.

What you are suggesting (10-20ns) will move the waveforms (especially BCK) toward the sinewaves and the transition points will become less defined. This leads to jitter as far as I know. Though it still can be acceptable in non-o/s applications.

If you can shed more light on for what in the analog part are used +5V and -5V supplies, it will be more than welcome.

Pedja

[HtP]

Pedja

What you are suggesting (10-20ns) will move the waveforms (especially BCK) toward the sinewaves and the transition points will become less defined. This leads to jitter as far as I know. Though it still can be acceptable in non-o/s applications.

1. Delay is not important as long as the delay is equal for all inputs.

2. Delay has no influence on the definition of the transition as long as the noise of the delay element or the noise of the inputstage does not significantly cause jitter.

3. The noise bandwidth of the pnp input stage is less than 5MHz, the noise density of the input stage is far below 1k. The resulting integrated noise is far below that for the input filter.

3. Maximum specified input rise time is 35nsec for all applications.

4. An input RC filter with R = 1k and C = 10pf has a bandwidth of 15MHz. The noise of this resistor in that bandwidth becomes 0.13nV/sqrtHz * sqrt(1k * 15MHz) = 16microVolt. If the RC filter is driven such that the output voltage equals 400mVpp, the slew rate at 200mV will be 50nsec/V.

The resultant jitter will be 16microVolt * 50nsec/V = 800femtoSeconds or 0.8psec rms.

This will cause noise which is .8psec/22.67usec or -149dB down wrt full scale.

I think this can be accepted.


regards,

[Bricolo]

Henk, I hope you have some hints about that


On another topic (http://www.diyaudio.com/forums/showt...006#post370006 ) stefanobilliani was talking about pin4 being a (11.xxxx MHz) input. In fact he was "wrong" because he was reffering to the TDA1541 (non-A) datasheet.

I wouldn't be surprised if this is still activated on the TDA1541A, but just undocumented.

Do you know something about that?

[HtP]

Stefanobilliani was talking about pin4 being a (11.xxxx MHz) input. In fact he was "wrong" because he was reffering to the TDA1541 (non-A) datasheet.

I wouldn't be surprised if this is still activated on the TDA1541A, but just undocumented.

Do you know something about that?

Pin 4 is activated on the TDA1541A.

regards,

[siu sin man tho]

hi,

if U want TDA1541a info.pls email to me to collect the PDF file.

this is my new design which use parallel (two) tda1541a NOS.
DAC with CS8414 contain I2S (SYN-SCK-SDATA) & CS8412/8414 can run use dip.switch setting for syn mode or aysyn mode.

thanks

thomas

www.diyaudiocraft.com

[Bernhard]

Hi Thomas,

looks very nice, maybe before making more of it, better wait what comes out from the low voltage I2S signal swing thread


Bernhard

[HtP]

Originally posted by Pedja
Henk, thanks for the input.

If you can shed more light on for what in the analog part are used +5V and -5V supplies, it will be more than welcome.

Pedja

Logic in the TDA1541(A) is current routing logic, in general between the -5V and the +5V pins. The logic swing is some hundreds of millivolts. Supply current is nearly constant, only a very small capacitive spike flows into the substrate.

Current reference generator for the output current is between -5V and -15V. Output current from the dac comes out of pin 6, 25 via diode switches or comes out via the +5V pin 28 by darlingtons. This means that complementory output signals L+R flow in supply pin 28.

regards,

[Bricolo]

Originally posted by HtP


Pin 4 is activated on the TDA1541A.

regards,

Could you give us some more details?
I know that pin4 is activated in the TDA1541A, since it is the right channel digital input, when set up in simultaneous mode.
What I wanted to know, is if the pin4 can be used as a SCK input when the DAC is set up in I2S mode.

Thanks
Alex

[siu sin man tho]

hi Bernhard,

very thanks for your comment.

this circuit was one of Germany friend send to me & I reference several more then Layout the PCB.

http://hjem.get2net.dk/torbenk/dualdactube.htm

http://users.podolsk.ru/boga/DAC.html

http://www.ndh.net/home/kboehm/T-DAC-P2.htm

Sorry I had a little misunderstanding that

better wait what comes out from the low voltage I2S signal swing thread

the I2S lead out can used for several purpose. one of the purpose was for the coming re-clocking parts.
But some of the diyer not like it. So I setting for options.
This several days I was testing this PCB & testing the Power transformers.
I collect this which prepare for this PCB & the output stage which use 6X4/diode with 6C45,EC88,EC86,EC8010 or 6DJ8 SRPP circuit. Also, I had another test need to test is, if the user use 6C45 or EC8010. Then use the pre-amp output 10K:600ohm to output.
I don't know the performance but i will test in detail.

pls see the power transformers.

thanks

thomas

[HtP]

Originally posted by Bricolo

What I wanted to know, is if the pin4 can be used as a SCK input when the DAC is set up in I2S mode.

Thanks
Alex

As far as I know, yes, but the designer told me that it was not (longer) needed. I have no experience with it.

regards,