Lets do the maths, to buy them directly from TI is USD$2.90 per qty 1K or for qty 1-99 is USD$5.34.
Adeleparts2010 per 1pcs is $2.74.
So.....how do they sell them below their cost price ???
Adeleparts2010 per 1pcs is $2.74.
So.....how do they sell them below their cost price ???
I'm fairly sure they're fake but just quoting the TI website price doesn't tell you what quantity users in China are going to pay.
I have seen one tenth as a common ratio between Digikey prices and volume pricing agreements. But I don't know about these op-amps.
Consider the price of your receiver, your phone or your TV. At Digikey prices you could not even buy a fraction of the raw components.
Consider the price of your receiver, your phone or your TV. At Digikey prices you could not even buy a fraction of the raw components.
If you buy transistors and chips from randoms on eBay/Amazon these days you will almost certainly get fakes, be smart and don't take the risk.
In general I agree. My rule of thumb is no power transistors, e-caps or op-amps from Ebay. I took a chance on the AD797 due to the extensive feedback and quantity shown. That has reinforced my rule not to buy those components online.
But it is sometimes not so simple. I have bought small test quantities from unknowns and ended up with what I needed and otherwise could not have bought. (One rack I am working on has 8x3x2 + 8x2 + 4x4 = 80 op-amps in it. There are six racks. So 480 op-amps.) One unknown supplier that I tested with two small orders and then one larger order has successfully delivered 120 of an important component and each batch has passed a battery of tests including using a notch filter to make measurements below the 120 dB range of the test equipment. [And a 60 dB gain LNA to verify noise performance.]
Anyways I did not buy the OPA1612 but someone else did and mentioned it to me. So I searched and saw that thousands of those had been sold also. So I wanted to know what others had found, if they had tested and verified their purchase.
I wonder if the OPA1612 are like this:
Fake OPA1612 from China
I have done similar small test batches and examination of some other components such as solid polymer capacitors, polypropylene capacitors and certain difficult to obtain very low noise transistors. It enabled the use of better components (actual measured performance) that otherwise would be way out of the budget. But it is a lot of work. [But I have enjoyed learning/building the LNA, notch filter, discrete ultra low noise supplies, etc.]
But it is sometimes not so simple. I have bought small test quantities from unknowns and ended up with what I needed and otherwise could not have bought. (One rack I am working on has 8x3x2 + 8x2 + 4x4 = 80 op-amps in it. There are six racks. So 480 op-amps.) One unknown supplier that I tested with two small orders and then one larger order has successfully delivered 120 of an important component and each batch has passed a battery of tests including using a notch filter to make measurements below the 120 dB range of the test equipment. [And a 60 dB gain LNA to verify noise performance.]
Anyways I did not buy the OPA1612 but someone else did and mentioned it to me. So I searched and saw that thousands of those had been sold also. So I wanted to know what others had found, if they had tested and verified their purchase.
I wonder if the OPA1612 are like this:
Fake OPA1612 from China
I have done similar small test batches and examination of some other components such as solid polymer capacitors, polypropylene capacitors and certain difficult to obtain very low noise transistors. It enabled the use of better components (actual measured performance) that otherwise would be way out of the budget. But it is a lot of work. [But I have enjoyed learning/building the LNA, notch filter, discrete ultra low noise supplies, etc.]
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I bought some HP RF mixer chips from that vendor, and they were clearly inferior to known genuine HP chips.
You need known genuine parts of the same type number for a benchmark to compare the cheap China chips to.
You need known genuine parts of the same type number for a benchmark to compare the cheap China chips to.