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  1. #1
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    Low drop voltage regulator

    I'm designing a battery operated circuit where the load current will be max. 50mA.

    Can I use LP2950-3.3V or MIC5236-3.3V?. Which is better. Or do you suggest other IC.

    Thanks in advance.

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    Re: Low drop voltage regulator

    looks like either will be ok
    TI and Micrel are reliable manufacturers.
    what voltage will you be providing to the regulator?
    what is the maximum current at turn on or turn off?
    if its battery operated, why are you using a regulator?
    i suggest a 1 uF cap on the input voltage and on the output voltage
    (unless the data sheet specifically says otherwise)



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    Re: Low drop voltage regulator

    Hi,

    Which is better.
    "Better" in which regard?

    Beauty? Long legs?

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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    Re: Low drop voltage regulator

    What about the AMS1117 3.3V ? I as well as many others sell them on eBay for not much money. As wwfeklman said it is important to use the manufacturer’s recommendations as to the input and output capacitors.



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    Re: Low drop voltage regulator

    Can I use LP2950-3.3V or MIC5236-3.3V?. Which is better. Or do you suggest other IC.
    It will be useful to remember that they are basically linear regulators and waste energy- that may be some consideration for battery operated devices.

    Use the regulator only for the part that demands regulated voltage. There are lots of low drop regulators in the market.



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    Re: Low drop voltage regulator

    You should have included the datasheets in your message such that people here could perform a quick analysis and comparison of parameters.

    The only other parameter I would consider what is the variation the regulator's ground pin current vs load. More so near the dropout threshold.

    I have used the LP295x regulator extensively for many years, and can tell you that it is not very good in that respect.
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    Re: Low drop voltage regulator

    You didn't specify relevant application parameters except 50 mA current. How about the input voltage, expected quiescent current? AMS1117 has >1 V dropout voltage, no true LDO.



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    Re: Low drop voltage regulator

    The AMS1117 has a dropout of 1.1V at 0.8A, at 50mA the dropout is much less.



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    Re: Low drop voltage regulator

    About 0.7 V at low currents, if you call it LDO, I won't.

    Also quiescent current isn't mind blowing. Again, if we know the requirements, we can suggest an appropriate regulator type.



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