Voltage regulator cross-reference

[raregtp]

Hey all....hoping someone can help me with this. I have a couple voltage regulators I'm trying to cross but not having much luck.

The first is:

A1
AS1117L-18
B0640 25

The second is:

A1
AS1117L-33
B0640 28

I know the AS stands for Alpha Semiconductor, and I think I've found a datasheet for the AS1117L-33, just can't find anything for the -18. Ultimately I'm looking to cross these over to parts that I can get now, as all I'm finding similar are AZ1117 regulators.

If anyone can assist it would be much appreciated. And.....if you can tell me what they cross to, can you also share your source?? Thanks!

[budm]

Re: Voltage regulator cross-reference

It is just a 1.8V fixed regulator.
1117 series regulator.
https://cdn.badcaps-static.com/pdfs/...5be0cd1d45.pdf

[raregtp]

Re: Voltage regulator cross-reference

Thanks.....this is my first foray into replacing a voltage regulator. I've recapped tons of stuff but decided it's time to take thing further.

So....the important part of the identification is the 1117 and the 18 (or 33) in the part number. Is there any type of a naming or part number standard when it comes to the rest of the letters I see when looking up 1117 series voltage regulators? To be fair, I'm an IT engineer and VERY used naming standards and "patterns"...so just looking to learn how it's done on electrical componants.

Thanks for the quick answer!!

[redwire]

Re: Voltage regulator cross-reference

For semi's, look at prefix, root part number, and suffix. Last line is typically mfg plant and lot number or datecode. A logo can also help ID a part's mfgr.

AS manufacturer Alpha Semi. This is AMS1117
1117 root p/n and possibly package L (which I could not find an exact match) or L for low power etc.
-18 fixed output 1.8V
-33 fixed output 3.3V
-50 fixed output 5.0V etc.

These Vregs are a commodity item, jellybean common, so many companies make them in the gutters of china and it can be hard to find the original.

[raregtp]

Re: Voltage regulator cross-reference

So is it fairly safe to say as long as I'm getting a 1117-18, and the pin/package looks the same and is the same size as what I'm replacing, that generally there won't be an issue?

[stj]

Re: Voltage regulator cross-reference

exactly.

have this:
https://www.aliexpress.com/item/32944697105.html

[sam_sam_sam]

Re: Voltage regulator cross-reference

exactly.

have this:
https://www.aliexpress.com/item/32944697105.html

Thanks for posting this I need some of them regulators

[dicky96]

Re: Voltage regulator cross-reference

Also seen 1117-ADJ for adjustable ones, plus some just marked 17-18 for the 1.8V fixed type

[budm]

Re: Voltage regulator cross-reference

The question to OP, are the regulators bad?

[redwire]

Re: Voltage regulator cross-reference

exactly.
have this:
https://www.aliexpress.com/item/32944697105.html

You've had luck with that seller? I never tried them.

The original (father) part is LM1117 with a max. Vin of 20V.
Note some variants have a lower input voltage rating IR is 7V, AMS is 15V. They are rarely run up high because of high heat generation.

[stj]

Re: Voltage regulator cross-reference

You've had luck with that seller? I never tried them.

The original (father) part is LM1117 with a max. Vin of 20V.
Note some variants have a lower input voltage rating IR is 7V, AMS is 15V. They are rarely run up high because of high heat generation.

seller is good, i have that kit here now.
as for max input voltage, it actually depends on the output voltage.
the package can only drop so much.

[raregtp]

Re: Voltage regulator cross-reference

Yea....working on a couple LP-2407 Gateway LCDs.....six of them to be exact. Four came back to life after recapping, the other two had obvious bad caps but didn't respond after recapping. With the help of this forum, went on to troubleshoot and identify my first bad regulators. One mainboard had two 1117s that were bad, a 18 and a 33. The other board had a completely different 1117 that was bad. That one in particular I had an easier time cross-referencing, probably because it was an AZ-1117 regulator.