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5V regulator outputting 5.9V and more.

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Siwastaja:
Yeah, while old-school non-low-drop linear regulators such as 7805 are still fairly OK, avoid most old low-drop regulators, as they tend to have strict requirements for the exact types and values of output capacitors.

Market is full of regulators specified to be stable with ceramic output capacitors; use them whenever possible. Also try to find one which is happy with lower capacitance, allowing smaller solution area and possibly lower total cost. Some are OK with 1uF while others require 10uF.

Using specific types and values of output capacitors in your BOM tends to eat away the price benefit you get from a cheap, old-tech regulator.

Simon:
I thought it was a newish regulator as it has the load dump capability, in the past I only ever found 5V regulators that needed wrapping in protection circuitry and rarely accepted auto range voltages. Seems like they took and old design and beefed it up but it's still the old design. I will remove it from my parts library, while the input will withstand the auto environment clearly as an overall part it will not survive the full range of conditions.

MagicSmoker:

--- Quote from: Simon on December 09, 2019, 11:47:06 am ---I thought it was a newish regulator as it has the load dump capability, in the past I only ever found 5V regulators that needed wrapping in protection circuitry and rarely accepted auto range voltages. 
--- End quote ---

I would be very wary of trusting any regulator whose datasheet says it can withstand "load dump" unless the manufacturer certifies compliance with ISO 16750-2 (or the older 7637-2) and specifies the minimum series resistance needed to do so.

Good practice with any kind of automotive product is to add at least a 24V nominal TVS diode, preferably in a SMC or larger package, to provide the bulk of load dump protection. That said, whaddya need an LDO for to provide 5V with a 12V nominal input? If it's to maintain operation even during engine cranking that is not something I would entirely entrust to minimizing the dropout voltage; a blocking diode and some bulk capacitance before the regulator would be much more reliable (and give better load-dump tolerance to boot).

Simon:
TVS is for spikes, I don't know what they mean by load dump buh I take it to mean the surges that should not exceed 40V. I have a 33V TVS

MagicSmoker:

--- Quote from: Simon on December 09, 2019, 12:40:13 pm ---TVS is for spikes, I don't know what they mean by load dump buh I take it to mean the surges that should not exceed 40V. I have a 33V TVS

--- End quote ---

"Load dump" is the term for the voltage overshoot from an alternator that occurs when a heavy load is suddenly disconnected (usually the battery while it is being charged, but it could be any heavy load like electric power steering or the like). An "okayish" article on load dump is here:

https://www.electronicdesign.com/power/eliminate-those-automotive-load-dump-circuit-protection-headaches

You definitely want to get a copy of ISO 16750-2 if you are making commercial products for on-vehicle use.

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