Part Number: LM, Maunfacturer: National Semiconductor, Part Family: LM, File type: PDF, Document: Datasheet – semiconductor. General Description. The LM LM are monolithic integrated circuits that in this data sheet are a family of standard inductors and flyback transformers. LM datasheet, LM pdf, LM data sheet, datasheet, data sheet, pdf, National Semiconductor, Series SIMPLE SWITCHER Step-Up Voltage.

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By using our site, you acknowledge that you have read and understand our Lmm2577 PolicyDxtasheet Policyand our Terms of Service. I have a hard time fully understanding the datasheet of LM I bought this product that has a LM in it and the specifications indicated by the seller that it can have a maximum output current of 2A with a maximum input current of 3A.

When I tried testing it, it seems that it can handle more current than 3A and i’m just too scared to test it out as I might break lm2577 product. I tried scanning through the datasheet and I fail to see its maximum input current. What I actually need: I need to boost a 3V source to 15V and this is nicely done by the product. But the current isn’t the same because I need about 2.

Adjustable DC-DC Booster- LM2577

I only get 0. If it isn’t possible to actually do it with this product, what are my other alternatives? First, always get your datasheet straight from the manufacturer. The version you linked to is dated TI released a revised version in April While unlikely here, there could have been changes made, and you wouldn’t know.

It’s a good habit to get into. The output switch current has 6A listed as an absolute max, and 3A operating. This is your maximum input current. To see why, let’s take a look at the datasheet again. The switch switches the input current to ground through the inductor and sense resistor.

This is how a basic boost regulator works. Finally, let’s do a sanity check with the data you provided. That is pretty abysmal efficiency for a modern SMPS, but not outside of reasonable for the LM25xx era, and as much of a boost as you’re trying to get.


Put another way, you’re putting 9W into the regulator, and getting 6W of useful power out. The other 3W is wasted as heat.

If you’re trying to get 15V at 3A, this part is not going to do it. The output switch can’t handle it. Even if the switch was up to it, the 3V source would have to supply over 20A. Find a different, more modern part with synchronous rectification, and while you’re at it, reevaluate whether you really need to use a 3V source.

It’s just making life harder. Because it is a boost converter and you can’t break physics. Power is conserved, and you lose a bit or more than a bit of power to the regulator i.

If you want 15V 2. If you read the datasheet of the LM, it has an absolute maximum output switch current of 6. It’s not going to work. By clicking “Post Your Answer”, you acknowledge that you have read our updated terms of serviceprivacy policy and cookie policyand that your continued use of the website is subject to these policies.

Home Questions Tags Users Unanswered. Question on LM Ask Question. Henry Lachica 8 6. Several things to look at here There is a very good chance that ” is a Chinese counterfeit so the chip specs may be different from the TI part, and the board specs are probably on the optimistic side.

So what did the seller mean by Input Current: We will use solar panels so that would do it. We would be able to supply 0.

So if we stack it up, we’re gonna have a total of 4V and 6A, as a source tested the solar datasjeet during a very hot day. These solar cells need to go inside a solar charger controller that’s why we need to boost it to 12V. The problem is the current out would not be enough when we use a boost converter.


I’m actually looking into another product but I’m not sure if it’ll work again if the same inputs were datasheft. HenryLachica The seller meant exactly what they said. What you’re wanting is physically not possible.

LMADJ Datasheet(PDF) – National Semiconductor (TI)

There isn’t a product in the world that will make that possible. There are may boost converters available. Digikey might be a good place to start. Okay, that I understand. The next question is can the LM handle more than catasheet If so, I’d have no problems with it.

I can’t see any specifications on the datasheet that refers to the maximum input. What does the “absolute maximum output switch current” and the “operating maximum switch current” mean? See Matt Young’s answer above. The maximum switch current is exactly that: Granted, it’s a datasehet difficult to calculate exact switch current from a desired output current, but the point is, at a max switch current of 3A, it’s definitely not going to give you 13A switch current is always higher than output current.

I’ve seen and looked into it. I’m trying to work around it.

components – Question on LM – Electrical Engineering Stack Exchange

The source is actually a solar panel. With the solar panel, it’s actually possible to have that kind of supply. The supply of our tested solar panel had a voltage of V and a current of 6A. So we’re actually having problems of boosting both the current datzsheet voltage simultaneously. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Ratasheet. Post as a guest Name. Email Required, but never shown. Post Your Answer Discard By clicking “Post Your Answer”, you acknowledge that you have read our updated terms of serviceprivacy policy and cookie policyand that your continued use of the website is subject to these policies.