A Bridged TDA2050 for Single Supply

[palstanturhin]

Need to make one for car use. No virtual ground possible...
Running from single +24V...

Will it:
A) Explode?
B) Smoke?
C) Do nothing?
D) WORK?

Yes, the zobbels...

Thanks for your help!

[sregor]

Should work fine. Looks like Rod Elliots simple bridge circuit, with supply voltage divider for inputs. Simplest Ever Bridging Adapter for Amplifiers
I am presuming you used a separate supply circuit - seems it would have been just as simple to make a minus 12 supply as a +24. Just my 2 cents. Good luck.
BTW I like your connection of the cross resistor to the other side of the coupling cap.

[palstanturhin]

Decided to go the "hard way" and build an SMPS for this.
SMPS works fine but does anyone see any problem with this?



Its a subwoofer amplifier...

And it's oscillating - a lot!

[AndrewT]

Can you attach an active filter to a chipamp?
I think you may have to do those separately.

[palstanturhin]

Ok...

Andrew is once again right!
I made the filter passive, and ofcourse it works perfectly!

Thanks!

[sreten]

Originally Posted by AndrewT

Can you attach an active filter to a chipamp?
I think you may have to do those separately.

Hi,

Yes you can. But typically you take a unity gain active filter circuit,
and change the connection from the output to the unity gain point
of the feedback loop, i.e. connect the 3.3u to - in of the amplifier.

As shown the amp gain will make it oscillate like crazy.

To work accurately the lower feedback resistor has to be quite a bit
lower in value than the resistors in the active filter network I recall.

rgds, sreten.

[AndrewT]

Thanks.
I'll try to draw that out and see what it looks like.

[sreten]

Originally Posted by AndrewT

Thanks.
I'll try to draw that out and see what it looks like.

Hi Andrew,

we have been here before I think :

high gain 2nd order high pass active filter topology

rgds, sreten.

[naxilla100]

check this out
just change the power ic to 2040 or 2050
YOUR ic can be an active filter by its self.....

[sregor]

Originally Posted by naxilla100

check this out
just change the power ic to 2040 or 2050
YOUR ic can be an active filter by its self.....

The schematics are doing exactly what sreten suggested - using the signal from the inverting input for the Sallen and Key circuits.

Another possibility would be to use a voltage divider (two resistors) on the output - especially if you wanted to change the Q of the circuit by adjusting the signal fed back. (if signal fed back is greater than twice the signal in, with equal resistors and equal capacitors, you get an oscillator.) YMMV