I need to order some more 1N4007s. I usually stick with OnSemi or Vishay, but looking at the other options (some cheaper) on Mouser, I wondered: What, if any, difference is there between the big name brands and the others? Or to phrase it another way: Do you just buy the cheapest available 1N4001-1N4007 rectifiers available from a trusted source, a la Mouser, Digikey, Arrow, etc?
Yes
It is hardly important at mains frequency, some OCD advice is there on the net for using Schottky devices instead of regular 1N4007 in mains rectifiers.
And it is a fairly common part, no critical technology involved unless you need military or medical grade parts.
Some claim it improves the sound.
I fail to understand how the supply, after conversion to low voltage, rectified, and filtered, would improve, particularly by using diodes not even optimal at mains frequencies.
Buy a lot of the cheapest good ones you can get, prices might go up, OTOH you are adding to the shortage.
MC Taiwan are good, used in industrial applications here.
May be cheaper than the others in your market.
It is hardly important at mains frequency, some OCD advice is there on the net for using Schottky devices instead of regular 1N4007 in mains rectifiers.
And it is a fairly common part, no critical technology involved unless you need military or medical grade parts.
Some claim it improves the sound.
I fail to understand how the supply, after conversion to low voltage, rectified, and filtered, would improve, particularly by using diodes not even optimal at mains frequencies.
Buy a lot of the cheapest good ones you can get, prices might go up, OTOH you are adding to the shortage.
MC Taiwan are good, used in industrial applications here.
May be cheaper than the others in your market.
I usually get the cheapest ones Mouser has for 1N4007, UF4007, 1N5408, 1N4148’s, all manner of zeners, axial schottkys, and full wave rectifier blocks. None of these types are particularly critical. Also bought a couple of full ammo boxes of surplus 1 amp diodes for use when “I don’t care what it is as long as it’s a diode”. For flat-pack ultrafast or schottky im partial to Vishay.
I have a feeling there are just a few 1N400x production lines running, and the price we pay at DIY is a lot more about how many layers of distribution and packaging are in the way.
But of course there is also a good trade in rejects, both outright duds and marginal under-specs. So I would want to know my retail dealer, and the brand he says he sells.
But of course there is also a good trade in rejects, both outright duds and marginal under-specs. So I would want to know my retail dealer, and the brand he says he sells.
Are you working at high voltages, the 4007 is 1 kV?
Nothing is for free and the 4004 and below have lower forwards voltage drop, so less heat
Nothing is for free and the 4004 and below have lower forwards voltage drop, so less heat
I can't be sure but I guess all 4001-4007 diodes from some manufacturers are the same (at present time). They only have different markings. It can be easily checked by measuring Vf.
That's why I buy only 4007-marked parts. For voltages < 100 V I often use Shottky.
Voltage Through-hole axial package Surface-mount package 1 A
(DO-41) 1.5 A
(DO-15) 3 A
(DO-201AD) 6 A
(R-6) 10 A
(R-6) 1 A
(MELF) 3 A
(MELF) 1 A
(SMA) 1 A
(SMA) 2 A
(SMB) 3 A
(SMC) 5 A
(SMC) 50 V 1N4001 1N5391 1N5400 6A05 10A05 SM4001 SM5400 M1 S1A S2A S3A S5A 100 V 1N4002 1N5392 1N5401 6A1 10A1 SM4002 SM5401 M2 S1B S2B S3B S5B 200 V 1N4003 1N5393 1N5402 6A2 10A2 SM4003 SM5402 M3 S1D S2D S3D S5D 400 V 1N4004 1N5395 1N5404 6A4 10A4 SM4004 SM5404 M4 S1G S2G S3G S5G 600 V 1N4005 1N5397 1N5406 6A6 10A6 SM4005 SM5406 M5 S1J S2J S3J S5J 800 V 1N4006 1N5398 1N5407 6A8 10A8 SM4006 SM5407 M6 S1K S2K S3K S5K 1000 V 1N40071N53991N54086A1010A10
(DO-41) 1.5 A
(DO-15) 3 A
(DO-201AD) 6 A
(R-6) 10 A
(R-6) 1 A
(MELF) 3 A
(MELF) 1 A
(SMA) 1 A
(SMA) 2 A
(SMB) 3 A
(SMC) 5 A
(SMC) 50 V 1N4001 1N5391 1N5400 6A05 10A05 SM4001 SM5400 M1 S1A S2A S3A S5A 100 V 1N4002 1N5392 1N5401 6A1 10A1 SM4002 SM5401 M2 S1B S2B S3B S5B 200 V 1N4003 1N5393 1N5402 6A2 10A2 SM4003 SM5402 M3 S1D S2D S3D S5D 400 V 1N4004 1N5395 1N5404 6A4 10A4 SM4004 SM5404 M4 S1G S2G S3G S5G 600 V 1N4005 1N5397 1N5406 6A6 10A6 SM4005 SM5406 M5 S1J S2J S3J S5J 800 V 1N4006 1N5398 1N5407 6A8 10A8 SM4006 SM5407 M6 S1K S2K S3K S5K 1000 V 1N40071N53991N54086A1010A10
1N400* are DIRT CHEAP, so WHY try to save cents?
Just buy known brands such as mentioned above, period.
Or *anything* sold by, say, Mouser/Digikey/Farnell, etc.
Why buy "mystery" ones from AliBaba which "might" be junk is way beyond me.
Just buy known brands such as mentioned above, period.
Or *anything* sold by, say, Mouser/Digikey/Farnell, etc.
Why buy "mystery" ones from AliBaba which "might" be junk is way beyond me.
There are differences between manufacturers. All of the diodes will be 1 amp and 1,000 PIV thus good for under 350 VAC by themselves and double that in a bridge.
What is different is the switching noise. That is not specified by the manufacturers but does vary greatly.
You can use small coupling capacitors from each side of the diode under test to a battery powered oscilloscope to look at it.
Some diodes in the past were so bad that the switching noise could even screw up TTL circuits.
Some folks report this as an audible difference.
What is different is the switching noise. That is not specified by the manufacturers but does vary greatly.
You can use small coupling capacitors from each side of the diode under test to a battery powered oscilloscope to look at it.
Some diodes in the past were so bad that the switching noise could even screw up TTL circuits.
Some folks report this as an audible difference.
How much extra heat can we be talking about with a one amp diode, that most of the time it would be conducting significantly less? I keep a handful of 4001’s on hand, but only for use in diode biased class AB amps for which the bias is not adjustable. EVERYTHING else gets a 4007 (if it handles any real voltage or critical that it not fail) or one of the je ne sais quoi units out of the ammo box (if it’s not).
If I get ringing and it matters, I put a snubber on the transformer secondary. Ultrafast get used in high frequency rectifiers, class H commutators, baker clamps and anywhere else that speed actually matters. Trying to use speed to prevent ringing sometimes works, but sometimes backfires.
According to the datasheet they are not all the same. Generally 1N4001-4004 are given one set of curves and 1N4005-4007 another.
You get higher breakdown by lower doping levels and this raises Vf at 1A, simple semiconductor physics
If you buy from a reputable source, you know that the parts have been sorted and are not the rejects. Saving a few pennies could cost you a blown transformer
I tend to buy from reputable dealers now.
I have bought Chinese/Ebay stuff and regretted it with failures.
I have bought Chinese/Ebay stuff and regretted it with failures.
I'm pretty sure the big manufacturers stopped manufacturing/binning specific voltage versions (in groups such as 1N4004 to 1N4007) and probably minimised the sample testing as well before filling orders for a particular marking. The two types of 1N4004 I have (10-25yrs old) test PIV to 1.5kV, as do the 1N4007 batches I have, and have very low leakage up to onset of PIV. Some others have done similar PIV testing of 1N4004-7.
What is different is that the UF4007 have noticeable (but low) increasing leakage current on the way to PIV, which occurs at circa 1.2kV.
Some brands of UF4007 I think can be found with a slightly smaller diameter lead or different metal used, which could affect Tj - although for diy I doubt many focus on the thermal cooling available from the leads as many applications never get near ratings, and many seem to just use a 3A diode if there is even a whiff of a sense of 'better to be safe'.
Imho, it's worthwhile sample testing what you have or get in anyway, for peace of mind, by using a 1kVdc insulation resistance meter.
What is different is that the UF4007 have noticeable (but low) increasing leakage current on the way to PIV, which occurs at circa 1.2kV.
Some brands of UF4007 I think can be found with a slightly smaller diameter lead or different metal used, which could affect Tj - although for diy I doubt many focus on the thermal cooling available from the leads as many applications never get near ratings, and many seem to just use a 3A diode if there is even a whiff of a sense of 'better to be safe'.
Imho, it's worthwhile sample testing what you have or get in anyway, for peace of mind, by using a 1kVdc insulation resistance meter.
You are totally right, in general. But we are talking about real-life 4001-4007 diodes. Actually, it is much cheaper now to manufacture all of them as 4007, so they are only marked differently. Manufacturers don't show this fact in datasheets.
Rather than asking about brands, the more important specification of type should be. 1N4007 is in the end the first one in the series and there are a couple variations from a variety of manufacturers that modify the design for a certain purpose.