Old thread but anyhow... Pushing the IC beyond it's max supply voltage may not allow the protection circuits to function properly. I'm not saying your parts are authentic, but even the authentic parts will only take so much.
I don't understand why people here will often push parts to or beyond their maximum ratings. I often don't go beyond 80 or 90%. If that doesn't get the job done, move on to the next stronger part.
i don't know about you guys, but national (TI) sends samples.
i have four LM3886 and a LM1765 (1785? 1875? i don't recall) from them.
the IC itself is the cheapest part of the entire amplifier... essentially free. transformer, plugs (in, out, power) caps (if you don't trust the opamp to do common mode rejection) and case are the 100% of the cost. The ICs themselves are literally free.
Maybe because i am in university and they need a university email?
i have four LM3886 and a LM1765 (1785? 1875? i don't recall) from them.
the IC itself is the cheapest part of the entire amplifier... essentially free. transformer, plugs (in, out, power) caps (if you don't trust the opamp to do common mode rejection) and case are the 100% of the cost. The ICs themselves are literally free.
Maybe because i am in university and they need a university email?
yes fakes are everywhere. i hate them. after buying 4 of them i was able to find 2 with reasonably similar frequency response. the sad part is, nowadays fakes are so hard to distinguish from genuine ones. i actually came across some that are even laser enscribed.
Although "buying" samples from National cost me a bit more than using Farnell, I felt the extra security of knowing I had genuine National supplied chips and that was worth the extra cost.
Pity they restrict samples to 5 only.
I would like to buy direct from the manufacturers using their distribution system that they have set up for small quantity samples.
Pity they restrict samples to 5 only.
I would like to buy direct from the manufacturers using their distribution system that they have set up for small quantity samples.
Hi,
old thread but trying to get some info regarding orginal LM3886's. Can I get guaranteed original LM3886 from from RS components . They have office in india but all items ship from UK warehouse
reg
prashant
old thread but trying to get some info regarding orginal LM3886's. Can I get guaranteed original LM3886 from from RS components . They have office in india but all items ship from UK warehouse
reg
prashant
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Hi, I purchased 3 batches of LM3886 with different prices and different look. I am afraid that all are fakes, I do not want to test them with putting in work, I want to avoid "explosion" in my home. All of them read ~2 Ohm between pin 4 (-Vcc), pin 7 (GND). Is it normal?
From where did you purchase them? If from aliexpress or dubious sites, might be they are fakes. But can't tell for sure.
You can use a mains bulb tester in line with mains in your amp with these lm3886, see if they sing or not.
I got mine from RS long back and they were genuine and worked well .
You can use a mains bulb tester in line with mains in your amp with these lm3886, see if they sing or not.
I got mine from RS long back and they were genuine and worked well .
Yes it is Aliexpress, 3 batches, but the prices were from several Euro, up to 15Euro per piece. I hoped If anyone can give me measurement pin5 to pin7 from confirmed genuine one or confirmed fake one.
Definitely not, but ... not too sure about your measurement technique.
Are they unmounted, with all their legs free in the air?
Besides, you do NOT use the Ohm scale to measure a chipamp (or any semiconductor), except in very rare occasions; normal is to use the diode scale, and it´s not rated in "ohms" at all.
It´s actually the voltage dropped through a junction when fed a couple mA.
I also suspect the "2 ohm" value,uncomfortably close to what a cheap meter will show across a short.
Yes.. so it is even more annoying that in the middle of all this scarsity.. there pops up Topping with a new, LM3886 based model!!! aargh
So we know now who snaps up all the chips
So we know now who snaps up all the chips
As I was testing home made PCB, with chip soldered on it, I measured 2 Ohm ( as this is cheap multimeter, yes it is short). When I could not find any error (short) on PCB, I suspected the IC. Soldered on PCB, or not soldered on PCB, all ICs have ~2Ohm (short) between pin 4 and 7.
