07 – new linear regulator tests

A project log for Universal LiPo/Li-ion UVLO (undervoltage lockout)

Feature-packed over-discharge protection. Set the cell-count (2S to 7S), minimum cell voltage and dip-time below threshold. Fully hackable!

JanJan 06/26/2019 at 19:305 Comments

Update 2019-07-15

I tested two of the regulators. Both work quite well and didn't release the magic smoke yet. Even after the the repeated inrush-current tests (repeatedly connecting the fully charged 6S lipo battery) with the load connected.

The MD7350H does indeed use the full 3% output voltage tolerance stated in the datasheet and is my least favorite part.

The much smaller ME6203 works perfectly up to 38V and limits itself when short-circuited. It puts out perfect 5.00V under up to 20mA load and has a smaller footprint than the MD7350H. Using bigger PCB traces on all three pins will wick away enough heat to ensure proper cooling at 5V/10mA out (max).

At 2.7µA current consumption with no load (µC in power down state) it's well within what I need for low battery discharge when the circuit cuts the connection. I think my next set of PCBs will use this regulator!

The SY6345's are still in their anti-static bag and will be tested next.

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Had to order at LCSC anyway... So why not search for chinese brand regulators again?

I ordered the following chips for further tests:

We'll see how they work in my application!


Simon Merrett wrote 07/15/2019 at 11:22 point

Awesome - glad to hear you have a contender part in the ME6203

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Jan wrote 07/15/2019 at 12:21 point

Yeah, for the currents needed it really seems like the better choice over an DC/DC regulator which does need much more power when in low load operation.

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Alan Green wrote 06/26/2019 at 21:57 point

I get the sense that a much of LCSC's stock is comprised of cheaply-bought, left-over half-reels from large production runs. The supply of these components might not be reliable, but they sure are fun to browse, buy and play with. I've learned a lot about LEDs this way.

And now you have me looking up regulator datasheets and practicing reading hanzi.

I, too, love LCSC!

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Jan wrote 06/27/2019 at 05:34 point

At least they claim everything is genuine. Have ordered lots of stuff there, not a single problem yet.
You're right about the stock. Some parts are "when it's gone, it's gone" and are not restocked just because...

Sorting and finding parts is quirky too at times!

When I need my parts quickly (or need really new or fancy stuff) I use Digikey etc. But I LOVE browsing LCSC, just can't help it :)

Especially the Asian brands have really sweet stuff for sooo little money. 99% of the datasheets are English too!

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Simon Merrett wrote 06/26/2019 at 21:00 point - it's like a sweet shop 

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