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Where should i connect power supply for this amp? Answered

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!



Best Answer 7 years ago

Post a link to your pdf so we are looking at the same sheet.


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:

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".


Well, something's wrong here. When I look up tda 2006 I get a 15 watt audio amp.

That's a standard amp symbol. The number on the chip or list tells what kind of amp it is.

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.

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 :)

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?

looked around a little more. i think the inverting input is the input ground, and the non inverting input is the positive input. right?