Balanced line driver, PCB layout share

I got some information from a german diyer about TAHT1646.I just buy few from ebay too,the chip is a good pin to pin alternative of drv134.but it is a bit costly.

thank you Dave(Dataman19),the input is very useful:)

to Junior,
the 300ohm resistor on my board was left for circuit debug.you can check drv134 datasheet page 9,10 for the details.
you can leave out it in general purpose.


Zang
 
would this work

Hi,
A complete beginner here but any advice would be great thanks.
I want to be able to connect a tape deck, cd player and phono preamp to a pair of active speakers. The speakers only have balanced inputs XLR.
For a bit of a project I was thinking I would build a BLD with a source selector switch on the input.
I was wondering though would I be able to get away with using the +12V and -12V on an ATX PC power supply? Ive a box of them here pulled from old PCs. Would I need to add extra regulation and if so does anyone have a link they could send my to.
The other question is would this approach wind up worse in terms of noise than just using an unbalanced passive solution?


Any ideas would be welcome
all the best
N
 
I vuilt two of these boards and when I fire them up I get -15V on the negative pin of the DIP8 socket, but a whopping +30V on the positive pin. Im inputing that voltage so it seems as though my input passes through unregulated. Now this happens on both so what could cause this? A faulty regulator, maybe, but two of them? I used TO92 style regulators with heatsinks mounted on them.
 
turn the positive regulator 180 degree.there are pins different of TO220 and TO92.
the attached is a pins direction.


H.B.
 

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digi01 said:
turn the positive regulator 180 degree.there are pins different of TO220 and TO92.
the attached is a pins direction.


H.B.


Thanks, but Im running with the L78L15 and it have the reverse pinout from the LM78LXX TO92 regulator and the same as the To220 regulator. At least according to the datasheet. This was the first thing I checked, but I didnt switch it around since the datasheet indicated the correct pin layout.
 
Hello Zang
Do I have to use for the balanced driver a regulated power supply or just any power supply will do the job.
I ask these because the balanced pre driver it uses +/-15V and you regulated power supp voltage min18V .
Do I miss something here?
Or the regulated power supply for the amplifier not for the pre balanced driver .
Please let me know .
Thanks
Greetings
 
Re: balanced line driver for BPA300

juluska said:
I'm preparing a BPA300 amplifiers ( http://www.shine7.com/audio/bpa300_2.htm) and i need a balanced line driver.
Can i buy a pair of these pcbs for dvr134? How?
What is the proper voltage and VA rating transformer?
And what about the rectifier bridge?
Are not necessary bigger filter capacitors before the regulation?
Thanks

They are available at www.assemblycraft.com
The need +-18V DC or +-15 if you bypass the onboard regulators.
 
Re: balanced line driver for BPA300

juluska said:
I'm preparing a BPA300 amplifiers ( http://www.shine7.com/audio/bpa300_2.htm) and i need a balanced line driver.
Can i buy a pair of these pcbs for dvr134? How?


I know that several people uses this solution whit the DRV134 and similar circuits to bridge their amplifier, but I would not recommend it.

DRV134 datasheet
The DRV134 (and DRV135 in SO-8 package) converts single-ended, ground-referenced input to a floating differential output with +6dB gain (G = 2).

The BPA300 (and almost every other LM3xxx-based amplifiers) have a unbalanced, single-ended input. To bridge this amplifiers you need to convert one unbalanced signal to one unbalanced, non-inverted and one unbalanced, inverted signal. The signals need to be unbalanced, referenced to ground, and not a floating differential signal.

The DRV134 is not suitable for the job and there can be issues when using it for that. The job can easily been done with a dual OP-amp and some resistors instead.