I've played around with these IC's with some success... simple.. nice sound..
These chips are often referred to as interchangeable. Looking at the schematics in the datasheets I noticed that the capacitor and resistor in series to ground (Zobel network?) is on the IC side of the large output capacitor in LM383 schematic and on the speaker side in the TDA2003..
Is there a preferred topology or does it even matter?
https://www.st.com/resource/en/datasheet/dm00028077.pdf
http://www.circuitstoday.com/wp-content/uploads/2009/03/lm383.pdf
I'm aware that both these chips are obsolete but I have a good stash to play with
These chips are often referred to as interchangeable. Looking at the schematics in the datasheets I noticed that the capacitor and resistor in series to ground (Zobel network?) is on the IC side of the large output capacitor in LM383 schematic and on the speaker side in the TDA2003..
Is there a preferred topology or does it even matter?
https://www.st.com/resource/en/datasheet/dm00028077.pdf
http://www.circuitstoday.com/wp-content/uploads/2009/03/lm383.pdf
I'm aware that both these chips are obsolete but I have a good stash to play with
It is a good question, which normally indicates the person giving a reply is not certain.
It is a zobel-network and it compensates impedance properties of the speaker. So, a first reply based on that logic would say put the zobel-network at the speaker terminals.
The zobel-network improves stability of the amplifier and therefore there is some sense in putting it at the amplifier chip output.
Anyway, if the output coupling capacitor was ideal, it would not make a difference. But, it is not ideal.
A pragmatic person would do as each datasheet recommends, dependent on which chip you actually use. There may be slight differences between the chips.
In case it is needed with one preferred option, I would put the zobel-network at the speaker terminals.
I have many obsolete ICs I enjoy. Perhaps I have become obsolete myself. But, at long as I am happy.......
It is a zobel-network and it compensates impedance properties of the speaker. So, a first reply based on that logic would say put the zobel-network at the speaker terminals.
The zobel-network improves stability of the amplifier and therefore there is some sense in putting it at the amplifier chip output.
Anyway, if the output coupling capacitor was ideal, it would not make a difference. But, it is not ideal.
A pragmatic person would do as each datasheet recommends, dependent on which chip you actually use. There may be slight differences between the chips.
In case it is needed with one preferred option, I would put the zobel-network at the speaker terminals.
I have many obsolete ICs I enjoy. Perhaps I have become obsolete myself. But, at long as I am happy.......
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