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  1. #1
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    help me to design const ct source?

    Hi ,
    i want to design 20mA const current source. But my supply(Battery) is varing from 3.45 to 2.2 V .... How can i maintain same current at all voltage levels? This ckt will be on for few mS/day . so during off state leakage current should be very small.say less than 1uA.
    anyone can hlp me to design?

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  2. #2
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    Re: help me to design const ct source?

    TI provides an IC with a current mirror and a 100uA current source embedded : see for REF200 component.

    It's maybe a quick'n'dirty solution but it should meet your requirements.



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  3. #3
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    Re: help me to design const ct source?

    Hi,

    Can U use a regulator.

    Madhukar



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  4. #4
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    Re: help me to design const ct source?

    for constant current a simple method use JFET ...

    use JFET as diode, and JFET Ids = constant current
    but you should be notic input voltage and maker sure JFET still work
    well



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