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Where should i connect power supply for this amp?


The part is tda 2006. i am going off of figure 15 on the datasheet. im not sure where to connect power supply ground and v+. also what is the difference between inverting and non inverting inputs (other random question). Thx!

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Re-design6 years ago
Post a link to your pdf so we are looking at the same sheet.
astroboy907 (author)  Re-design6 years ago
http://www.st.com/stonline/products/literature/ds/1452/tda2006.pdf
in the first schematic shown, the

vs+ is the positive power (pin 5)

vs- is the neg. power (pin 3)

output is pin 4

pin 1 is the normal input

pin 2 is the input if you want to invert the signal

this is a mono amp and you need two to make a stereo amp, but would make a loud practice guitar amp.
The part you mention is an op-amp.

An op-amp is a component, a part of a circuit.  It is not a complete amplifier.  If you want to use it as an audio amplifier, you will have to build a circuit around it.

The "typical application" circuit, shown on page 1 of the data sheet you linked to, shows one way to do this.  This circuit is a variation on the textbook non-inverting amplifier circuit,  explained here:
http://en.wikipedia.org/wiki/Operational_amplifier#Non-inverting_amplifier

The difference between the application circuit in the data sheet, and the easy textbook example, is that they've thrown in some capacitors so that the amplifier will not amplify DC.  I mean if you look at the circuit you can see it has an AC gain of R1/R2+1 = 22/0.68+1 = 33, and unity DC gain.

You said you were wondering where to hook up +V and Gnd.  Which I guess means you want to use this op-amp with a single sided power supply.  I.e. you don't have +V, Gnd, and -V.   To do this, I suggest the circuit in the attached picture, from p225 of Horowitz and Hill (2nd Ed.). Also in the picture, read the blurb on "biasing single-supply ac amplifiers".




single-supply-amplifier.jpg
Link to big legible version of that diagram picture:
https://www.instructables.com/file/FYQTPWUGGMMR482/
Well, something's wrong here. When I look up tda 2006 I get a 15 watt audio amp.
If it's not an op-amp, why does it have the same symbol, and the same pin outs? 

BTW, I just noticed that the data sheet includes an application circuit for use with single supply.  It's on page 7, figs 15 and 16.
http://www.st.com/stonline/products/literature/ds/1452/tda2006.pdf
That's a standard amp symbol. The number on the chip or list tells what kind of amp it is.
astroboy907 (author)  Re-design6 years ago
K... umm... trying to comprehend all that :) i think i am sort of getting it. i went with the single power supply circuit because all the rest had split power and current i think. One the typical application diagram, there is an +Vs (positive voltage) -Vs (ground) and a vi (the input?). oh well looks like i made a mistake and went with the single power supply circuit when i didnt need to? idk im lost now. i have an input voltage (+Vs), but is Vi the audio input?
Looks like it is. vi is the neg. and should be ground and that would be the input.
astroboy907 (author)  Re-design6 years ago
k so just one last time to see if i get it
going off of fig. 15

Vi = Audio input (non inverting)

+Vs = Positive voltage

-Vs = Ground (actually there is no -vs in this diagram. i am assuming the bar symbol under the speaker is ground)

So it looks like input is grounded with a resistor across it. also i would just connect v+ on the power supply to +Vs and it would be fine (no voltage/ current issues?) Thanks for this. was getting a little worried :)
astroboy907 (author)  astroboy9076 years ago
K. soldered it yesterday and ran into some problems. did entire figure 15 circuit, and got a loud power on click. nothing else. today i soldered it up without any other electronics. i can hear very faint music, but if i turn up the input enough, i get very loud clicks and buzzes in time to the music. but its only on really loud notes, and the speaker is 50x louder than when it plays the music. i have the Tip of a trs connector on the non inverting input. i think maybe that the speaker is creating some interference with the audio, as they are both connected to the same ground. Any ideas?
astroboy907 (author) 6 years ago
looked around a little more. i think the inverting input is the input ground, and the non inverting input is the positive input. right?