So this one goes all the way up to 60V but the question is will it over heat?

The whole point of going to switch mode regulators is so they do not overheat. Assuming it has actually been properly designed, it will not overheat, as long as you run it within the specified ratings.

 

It won't overheat if you drop enough voltage before the regulator.

 

The whole point of going to switch mode regulators is so they do not overheat. Assuming it has actually been properly designed, it will not overheat, as long as you run it within the specified ratings.

Yea, if you trust those Chinese ratings.

 

Yea, if you trust those Chinese ratings.

Yes, it is a point. But the published photo does have the HV version of the chip in it. You always run the risk of getting fakes. When I was organizing board assemble a few years ago, we even got a couple of different components that were fakes when ordering through official suppliers.

It won't overheat if you drop enough voltage before the regulator.

But if the power supply in question does have the HV part, there is no need to reduce the input voltage to limit heating. Any external resistors or zeners will generate heat just the same as a linear regulator, so what is the point of doing that?
This power supply should work ok as long as you do not try to draw a lot of current from it. It is not the voltage that will heat it but the current. I would add a poly switch to the 5V out, like ..
https://au.mouser.com/ProductDetail/Littelfuse/RXE110?qs=tyNvw8uZfHgTOOmVh7VbCA==
This will allow 1Amp to be drawn but limit it after a bit if you exceed that by a fair margin.

 

The point is...wasting a few watts does not seem to be the main issue here.

I have read dozens of reviews on those many different simple switcher modules, and the main complaint is....wait for it...

Overheating. (besides the ones that simply don't work)

I would at the very least get a few of those 10x10mm sinks and apply one to the chip directly and one directly below the chip on the other side of the board.

 

The point is...wasting a few watts does not seem to be the main issue here.

I have read dozens of reviews on those many different simple switcher modules, and the main complaint is....wait for it...

Overheating. (besides the ones that simply don't work)

I would at the very least get a few of those 10x10mm sinks and apply one to the chip directly and one directly below the chip on the other side of the board.

You may be right if these are fake parts. I have used Simple Switcher chips in products for years with no failures, other than when they are plugged in backwards

 

No, I don't think it's an issue of fake parts...it's more like not understanding how the ratings work, the regulator is rated at 6o volts and 2.5 amps...so they try to get the max amps at 5 volt output, with 60 volts at the input, and poof.

Example: https://forum.allaboutcircuits.com/...load-watts-volts-and-regulators-oh-my.146199/

 

No, I don't think it's an issue of fake parts...it's more like not understanding how the ratings work, the regulator is rated at 6o volts and 2.5 amps...so they try to get the max amps at 5 volt output, with 60 volts at the input, and poof.

Example: https://forum.allaboutcircuits.com/...load-watts-volts-and-regulators-oh-my.146199/

That's why I reckon a 1Amp Polyswitch is needed

 

I just spotted this..
https://www.aliexpress.com/item/1PC...ae84-4ea7-ab93-e988416e3630&priceBeautifyAB=0

 

WOW! THAT'S A LOT OF REGULATION DOWNWARD. Consider how many amps (or milliamps) your cell phone is going to draw. You're going to have to dissipate a lot of heat through that LM317 regulator. Lets assume you're only going to use 200 mA (and that may be a lot, maybe not). Lets also assume you're max voltage during operation is going to be 40 volts. You're going to have to drop 35 volts. 35 (volts) X 0.2 (amps) = 7 watts. That doesn't sound like a lot, but it is. That's 7 watts of energy you're going to be converting into heat energy. If you put this in an enclosed container it's going to build a lot of heat. Eventually it will fry.

A buck converter (BC) is a far better choice. Since I'm not real familiar with how BC's work I can't say for sure, but I believe they work on a similar principal to how PWM (Pulse Width Modulation) works. They're on for a moment and off for a moment. Depending on how long they are turned on and how long they're turned off you get an average voltage. If it's on 10% of the time and off 90% of the time (and they operate on a relatively high frequency) you get 1/10th of the total voltage giving you an average voltage. In your case, 10% of 40 volts is 4 volts (average).

The device you ordered is cheap for a reason. It isn't likely going to suit your needs. Like I said, if your cell phone draws 200 mA to charge, that's an additional (5x0.2=1) one watt, bringing your total dissipation to 8 watts. AND given that this is not a perfect world, there's going to be other draws on it as well. Wire does not conduct 100%. a 100% conductor is called a super conductor. So there's going to be even more losses. And your battery voltage (on your bike) is going to waste energy and drain the battery faster.

[edit] It's interesting they are calling this "REGULATOR" a "BUCK - STEP DOWN CONVERTER". It's just a regulator. Does not operate the way a buck converter does. At least not to my understanding.

[edit #2] https://en.wikipedia.org/wiki/Buck_converter

What you bought is a linear regulator.

Tonyr1084 - What are you talking about? How does a Cell Phone that has a battery voltage of 36VDC apply here? The poster is looking for a charger for his eBike and he wants to use the USB-C Charging port.
..
I have the same issue with a stupid TMU Juicer that my wife bought, It came with a detailed instruction manual and tells how to turn it on and off, how to load oranges and lemons - but the so called "Detailed" Instructions say nothing except that you attach the 36VDC Charger to the USB-C Port (actually it simply states "Internal battery is charged with the convenient USB-C Charging ports).
..
My problem is finding a USB-C charger for this juicer (since TEMU and the Seller does not provide one).
..
This is the juicer:
https://www.temu.com/goods_snapshot..._1738553534129_lzlkdb5dee&refer_page_sn=10032
..

 

Sorry... I just wanted to clarify that the reply posted was referencing 5VDC Cell Phone chargers and the OP was posting about a 36VDC eBike...

 

@Dataman This thread is from March 2018. Nearly 7 years old. It's been a very long time since anyone has reacted to this posting. Nevertheless:

Hello,
I am super new to electronics and working on a project where I want to connect a USB port to my Ebike battery.
My battery is 36V and 10 amp and I want to connect a USB port to charge my phone on the battery.
I have a step down converter to get the voltage to 5V but what about the amp's can it fry devices I connect, I think I am missing a componant.

The original post wanted to plug 36 volts into his phone using some sort of converter (link expired) to drop to 5 volts.

WOW! THAT'S A LOT OF REGULATION DOWNWARD. Consider how many amps (or milliamps) your cell phone is going to draw. You're going to have to dissipate a lot of heat through that LM317 regulator.

Somehow I got the impression we were talking about an LM317 regulator. That WILL have to dissipate a TON of heat. But I'm not the only one who started thinking about an LM317. So did bertus.

The step-down regulator shown in the link of post #6 will not work.
The LM317 is a linear regulator with a maximum working voltage of 40 volts.
The naming linear will tell you taht a lot of heat will be dissipated when current is drawn.

________________________________

Tonyr1084 - What are you talking about? How does a Cell Phone that has a battery voltage of 36VDC apply here? The poster is looking for a charger for his eBike and he wants to use the USB-C Charging port.

As mentioned before, this thread is 7 years old. I'm sure by now the TS problem has been solved. Or he's blown up a phone. Or the electronics on his bike. There is a limit (to which I don't know what that is) a charging port (USB-C) can take in before the electronics inside the device blows up. A cell phone requires a 5V source. That's where the charger comes into play. I have 110VAC chargers that drops the voltage to 5 volts (respectively). The TS wanted to use 36V regulated down to 5V. That's 31 volts that has to be turned into heat when using an LM317, which is what I was directing my comments at. Also as mentioned, those links have long since expired and it's not possible to look back at what those items linked to were. Were they an LM317? Can no longer tell. But again, I was not the only one who thought it was an LM317.

This post should be locked so nobody wakes the dead again. But I'm not a moderator, I'm just a member.