Texas Instruments NE555N NE555 NE555P General Purpose Single Bipolar Timer DIP8 50 Pack

These are what they say - 555 timers. This is more 555 timers than I will ever need, but for the price, it's a pretty good deal. I used a couple of the timers in a custom motorcycle taillight. They've been working for over three months, so I'd say they're good quality. Of all the ones I've had the pleasure to use, I've never had an issue with one not working or strange issues. Haven't found any with distraught pins or missing pins. I've used these both in a monostable and astable, and to sink and source current. For the record, most 555 timers (including this one) can sink a lot more current than they can source. They also source a volt or so under the supply voltage. Just beware, this can change LED setups, as they will need different current limiting resistors.

I was amazed at the price when I saw this ad. 50 NE555N 8-pin chips for $3.18. So, I bought them and received them on time in working condition. I've tested them all in a working timing circuit and they all worked. No burn-in for me, though. I didn't have the time for 50 units. All came with standard DIP 8-pin, a standard body and pins. However, they weren't marked. I had thought that with 50 units someone was trying to get rid of them all, but with the testing I did, I am fairly happy. I think I trust this supplier. They did come on a piece of plastic foam, which I am not happy with, some fall off rather easily, but most hold. I bought the chips, not the foam. I have had them 2 months and the few I've used haven't failed.

These did not come in an antistatic bag. This was probably the reason why 11 out of the 50 I received were defective upon arrival. I tested them using R1 = 1K, R2 = 100K, and C1 = 10uF. I cross checked the oscillation rate with another timer which was purchased from a different source. However, assuming that approximately 10 of 50 chips are defective (which seems to be about right, looking at other reviews), the price per chip is 7$ / 40 chips, which equals about eighteen cents per chip. Now, the cheapest through-hole 555 timers on Mouser are about thirty cents apiece. So despite the defective chips, you're still getting a good deal. Just make sure to test AKK of these when you get them. You don't want to use a defective one and then go around trying to find the problem. Don't know what to do with the defective ones? 'Cause the picture is relevant.

I have never wrote a review but felt compelled after spending 20+ hours trying to fix whatever was wrong with my design(it was working fine for two months). Finally gave up and threw my project to the side. Later I needed to use one of my other deigns that was working perfectly. I used these to build it. Needless to say it did not work. I spent 2-3 hours troubleshooting but came up with nothing but frustration. On a whim I replaced the chip with an old NTE I had laying around and BAM! it was working fine. I tested about 15 of these new chips and everyone of them would either not work at all, work for 2 minutes then fail, or work then fail after a second. I monitored output with my sillyscope. What I determined with multiple tests is that if the voltage and amperage on the supply is very low they will work fine indefinitely, think 9v battery. as soon as I bumped it up to very stable 12v 1A supply with a regulator it would fail with a nice puff of magic smoke. Insert the NTE brand timer and voila working perfectly. This product is garbage, and there is no way this was manufactured by TI.

These are not Legit 555s! I say this because the 1st 5 out of 5 I tested didn't behave normally. But yet, they're kinda neat as they do something that I like that would be much more difficult to design. The ones that I refer to have a fake (I think) T.I. logo on them, followed by NE555P. The 2nd line has HYC 3253H. Are they saying that these were made in the 32nd week of 1953??? Before my time, and 555s. I used these in an astable ckt to strobe 2, super bright LEDs at 100mA, at about 1Hz and 10% duty cycle. My components were 100K and 1M Rs, 1uF stacked metal film cap, 1N914 diode, and resistor in series with 2 LEDs as the load to ground. When powered up, I didn't get extremely bright pulses as expected. Instead, I got 2 different, ramped up dim levels, followed by the extremely bright pulse. I've never seen this before so I swapped 2 different Harris LM755Ns and an RCA CA555E into the ckt. They behaved normally. Then I swapped in a Philips 7555 CMOS version, which also worked fine. Finally, I added a bypass cap to Pin 5 and the devices behaved normally. But the cap should not have been required. Since my application was for strobes on RC airplanes, I might use these to simulate strobes/rotating beacons. I do give these 5 stars for showing me something I never expected out of a chip! If you want them to behave, >= 0.01uF Pin 5 to ground should do it.

I have a few older, genuine TI chips, and that, these are not. It is possible these are in fact TI, but if so, TI sold their manufacturing to someone with far lower standards. Even then, if these are TI, why does the photo show ST Micro's logo? These have crappy screen printing, with a low quality blob in place of TI logo, which of course does not affect the function of the chip but is an indicator of the quality of manufacture. Performance still is not up to par. Wave form is not very good, my three genuine TI 555s are 15 years old and perform better. All that said, the chips ARE 555 chips and DO perform consistently enough that they can be used for some things but they are not of the grade I expected.