I'm fairly new to this stuff and I'm building a preamp for my truck (semi). I thought I was so smart and ordered the ICs and sockets I need from mouser.com, to find that only one of the ICs I ordered was in the correct form for my use (apparently "PDIP" is what I need). That was the TI DRV134 (DRV134PA). The others, the INA134 and the OPA1602, I inadvertently ordered in some sort of miniature board-mount versions. I was able to find the correct version of the INA134 (INA134PA), but they don't have the OPA1602 in any version that is not a miniature board-mount. I need it from Mouser so I don't have to wait for shipping (I live not far from them).
Does anyone have a suggestion for an opamp IC that I could easily find in the larger PDIP form?
To answer a question this may have raised, yes I have a balanced line source and a receiver with balanced inputs. Both of these are in rear areas of the cab and are part of a fairly complex system I am building.
Does anyone have a suggestion for an opamp IC that I could easily find in the larger PDIP form?
To answer a question this may have raised, yes I have a balanced line source and a receiver with balanced inputs. Both of these are in rear areas of the cab and are part of a fairly complex system I am building.
Go onto Mouser and search for op amps.
Then filter by package and use "PDIP"
You can then filter by number of pins, number of amplifiers in a package, speed etc etc
Then filter by package and use "PDIP"
You can then filter by number of pins, number of amplifiers in a package, speed etc etc
Thank you so much; I didn't know you could easily search for ICs on Mouser in this way. I was able to find one (TI OPA604)
I have used the Aries adapters for SOIC, MSSOP and TSSOP as they fit the conventional DIP spacing -- they are a bit expensive. DK carries 'em
Most big electronics companies now have good search facilities.
When I were a lad in 1980 it was the Maplin catalogue !
I would suggest the LM4562 from Mouser. It is a state-of-the-art op amp in performance; it is available in PDIP form and is relatively inexpensive.
The NE5532 is even cheaper still and the industry standard, and less susceptable to EMI
(the LM4562 is about the worst chip for this, apparently, unless you are careful to thoroughly shield RF from it and its pins, it may bite you)
(the LM4562 is about the worst chip for this, apparently, unless you are careful to thoroughly shield RF from it and its pins, it may bite you)
I may wrong but I guess PDIP is the same as DIP. Possibly this fact can help TS.
If not then: there isn't much differential line drivers at all (DRV134), and DIP is a bit outdated case type for actual manufacturers, so some other case type plus DIP-adapter may help (as it was suggested).
If not then: there isn't much differential line drivers at all (DRV134), and DIP is a bit outdated case type for actual manufacturers, so some other case type plus DIP-adapter may help (as it was suggested).
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PDIP = Plastic DIP
There are other types of DIP packages as well, so DIP alone is ambiguous.
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yes I was aware but thank you for being on the safe side and pointing it out.
I did run into a different issue though, which is that I inadvertently ordered an OPA2134 in lieu of the INA2134 (the INA not having a PDIP version). Which is a straight opamp (a nice one apparently) rather than a balanced line receiver opamp (the INA2134). That's not a problem because I referred back to the resource I was fortunate enough to find previously https://www.electronics-tutorials.ws/opamp/opamp_5.html and reviewed how to implement a balanced line receiver using the straight opamp. I just want to ask what value resistor I should use (I am thinking 10k but unsure) for R1 = R2 = R3 = R4 (all the same value so it will be unity gain).
Oops. I forgot that it's the OPA604, not the 2134, that I had selected as the balanced line receiver. Too much going on. So my prior post is irrelevant. Sorry.
The circuit you linked to is fine as long as you aware of a couple of things.
If all the resistors are equal value then the voltage you see at the output will be twice the voltage at each individual input.
So if you apply 1 vrms to V1 and 1vrms (but now 180 degrees out of phase) you will get 2 volts rms at the output.
The other thing to be aware of is that the input impedance of each input is different unless fed from a low source impedance which in that case probably doesn't matter that much.
Using 10k resistors sets the input impedance for the V1 input at 6.66k and for the V2 input it is 20k.
So the circuit needs a very low driving impedance to operate correctly.
If you scroll down the page you will see how to overcome that by adding buffers to the inputs.
If all the resistors are equal value then the voltage you see at the output will be twice the voltage at each individual input.
So if you apply 1 vrms to V1 and 1vrms (but now 180 degrees out of phase) you will get 2 volts rms at the output.
The other thing to be aware of is that the input impedance of each input is different unless fed from a low source impedance which in that case probably doesn't matter that much.
Using 10k resistors sets the input impedance for the V1 input at 6.66k and for the V2 input it is 20k.
So the circuit needs a very low driving impedance to operate correctly.
If you scroll down the page you will see how to overcome that by adding buffers to the inputs.
Hmmmm....I've used LM4562s throughout my gear and never had a problem IF you properly bypass (100nF MLCC) the power pins right at the IC. I also put sufficient rolloff in the feedback (22-82pF, depending on circuit) to limit the bandwidth to 200KHz or so (don't need more than that, surely). Have you documentation of this supposed susceptibility to EMI?
That's interesting.....does seem to indicate some susceptibility of the 4562 to HF interference. It IS 120 db down, and all my gear is in steel boxes, so I'm sure I couldn't hear it anyway.
There are more than a dozen spurs at or above -120dB so they'd all need to be integrated to gauge the total. In the most optimistic case they'd be all uncorrelated and would only add power-wise.
If you can't find an op amp in PDIP packaging, you might find it in an SOIC-8 package. There are adaptor PCBs to allow inserting an SOIC-8 package into a PDIP 8 socket or footprint, if all else fails.
Sensitivity of opamps to air coupled EM fields, especially of the LM4562/LME497X0 family | Audio Science Review (ASR) Forum
And Doug Self comments about it too in at least one of his books. There's also the variable 1/f noise issue https://e2e.ti.com/support/audio/f/6/t/415907
And Doug Self comments about it too in at least one of his books. There's also the variable 1/f noise issue https://e2e.ti.com/support/audio/f/6/t/415907
It certainly appears that the 4562 is best served in a shielded box and without a circuit design that amplifies noise 86db more than signal. Below is a direct quote from ASR:
"Of course the board with LM4562 may be put in a well shielded box and the problem seemingly disappears. I have had an “A-B box” to test 2 audio paths by immediate switching from one to another and the box allowed for level matching. It was built both with LM4562 and OPA2134. When closed with top cover firmly, both versions behaved almost same."
"Of course the board with LM4562 may be put in a well shielded box and the problem seemingly disappears. I have had an “A-B box” to test 2 audio paths by immediate switching from one to another and the box allowed for level matching. It was built both with LM4562 and OPA2134. When closed with top cover firmly, both versions behaved almost same."