I have a few at home from Mouser, I'll take a look. As far as I remember it says OP1656, not OPA1656.
Guaranteed parameters are tested. Typicals might be batch tested or even left for years without checking. Things like noise and PSRR are time consuming and expensive to test.I don't really know how opamps (and other stuff) are tested in production. Maybe someone knows and will tell us. I don't believe that every piece is tested. It is more likely that only a certain number of pieces from a lot are tested (a random sample). Based on that, whole batches are probably discarded, which can later be found on ebay. Among the specimens from the rejected series, most are probably completely correct.
I received one piece of 100k Dale RN55D resistor that has about 80k, bought from Mouser. It is the first time in 4 decades that I have found a new resistor with a fault.
Why package and test is done in low salary countries, while the wafer fab stays in the west.
I don't know, that's why I'm asking. I know that there are various methods, mainly with taking samples, testing, so if bad pieces are discovered, additional samples are taken from that batch and if there are still scraps, the whole batch is discarded. And with expensive and important things, everything is tested, responsible parts for airplanes, for example.
I just wanted to test it! They're genuine Mouser!
This fake/real talk annoys me.
Someone keeps coming up and claiming everything is fake! Whether they know it or not! Just like everything from China is supposedly fake, that's not true either!
Since I started using the OPAXXXX Soundplus, I haven't noticed a single fake. Even on eBay, I've only gotten genuine products.
This fake/real talk annoys me.
Someone keeps coming up and claiming everything is fake! Whether they know it or not! Just like everything from China is supposedly fake, that's not true either!
Since I started using the OPAXXXX Soundplus, I haven't noticed a single fake. Even on eBay, I've only gotten genuine products.
I have over twenty OPA1656, purchased from the first month they were released until last month.
All have OP1656 written, no "A".
Just answering the posted question, not getting into fake or genuine.
I hope this helps
Claude
All have OP1656 written, no "A".
Just answering the posted question, not getting into fake or genuine.
I hope this helps
Claude
Is this an original OPA1656?
That's what the ones i bought from Mouser look like.
All mentioned opamps are unity gain stable, so it won't oscillate. However, when the schematic is expanded with an additional output stage, this may change. I have published here on the forum the results for one copy of the Whammy headamp. Various opamps, various compensations and anti-oscillation measures. Some opamps work without the need for interventions. In my Whammy headamp, so far the OPA2604, NE5532 Signetics and Burson V7 Classic work without problems. I just take one out and stick the other in. When I move on to other opamps, I'll definitely need to play around. On the previous copy, it was the 1612 that gave me the most problems with wild oscillation (and it is not from China, and the adapter is BrownDog). 🤣
opa1656 works on my ha1452w adapter, but since it's replacing a dip-14 there was plenty of room for some 10pf caps across the feedback loop and an 0.1uf across the power pins on the underside.
I do note that many of your faster opamp datasheets recommend against adapters.
An adapter SOIC/DIP8 is a necessary evil for me, so that I can change the opamps. It is certainly better to solder directly to the PCB, but there is no playing with opamps. You lose something, you gain something as always.
I mostly use this adapter. It has the shortest connections from the opamp to the pins.
https://www.ebay.com/itm/393251890146
I mostly use this adapter. It has the shortest connections from the opamp to the pins.
https://www.ebay.com/itm/393251890146
I use only low temperature solder for my smd. As it melts at 140 degrees it is just to set the hot air gun to 200 and heat and take away or mount a new with a tweezer. It is so much simplier then hole mounted with leads.
I tried a few but it seems like chipquick lasts very long. Other brands can get hard in the syringe in about 6 months.
I tried a few but it seems like chipquick lasts very long. Other brands can get hard in the syringe in about 6 months.
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I use classical solders, lead and lead-free. I haven't burned any of the SMD parts so far. To desolder the TH components I bought a desoldering gun with a vacuum pump.
There is even someone whose eyes has carbon dating ability.I just wanted to test it! They're genuine Mouser!
This fake/real talk annoys me.
Someone keeps coming up and claiming everything is fake! Whether they know it or not! Just like everything from China is supposedly fake, that's not true either!
Since I started using the OPAXXXX Soundplus, I haven't noticed a single fake. Even on eBay, I've only gotten genuine products.
Of course, those SOIC to DIL adapters increase chances of oscillation, if only by increasing parasitic capacitance on the non-inverting input and between output and input pins. You get what you ask for.When I move on to other opamps, I'll definitely need to play around. On the previous copy, it was the 1612 that gave me the most problems with wild oscillation (and it is not from China, and the adapter is BrownDog).
Jan
So I had no choice, the Whammy design was done for a DIP8 opamp. That same OPA1612 on adapter didn't give me any problems in the second preamp. Everything is finished with compensation capacitors of 22pF to reproduce the square signal perfectly.
I have been buying reels of the TI OPA1692, they all come from Hong Kong. I order them from TI and that is who bills me for them.
A reel of 1,000 costs me $770.00 plus $12.00 for shipping.
I wonder what a fake would cost including relabeling?
A reel of 1,000 costs me $770.00 plus $12.00 for shipping.
I wonder what a fake would cost including relabeling?
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