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Linear led current regulator

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treez

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Hello,
We are seeking a linear led current regulator. We need it to be an error amplifier on a chip……..but the drive fet will be external, and the reference to the internal error amplifier will be input from an external source. We cant find anything offtheshelf…and digikey etc don’t allow us to sort on our requirements….does anyone know of anything?
The current sense resistor will also be external.
 

asdf44

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Sounds like you need this chip called an 'op-amp'....

I mean what value-add do you want from the chip? You buy LED drivers because they provide all the things you specified are external.

EDIT: Though I suppose by reference you just meant the current set point and you're looking for all the pwming and blinking? In that case I suspect you'll have to live with a chip that provides something you don't need. If it has internal low-side current regulators for example so be it, open load they'll be like open drain outputs.
 

kripacharya

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Sounds like you need this chip called an 'op-amp'.....
:clap: good call !

Alternatively just use an Lm317 current source config. But then the max current is limited.
 
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KlausST

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Hi,

and digikey etc don’t allow us to sort on our requirements
...and where are your requirements?
Voltage, LED current range, input signal type and range, precision, settling time...

Klaus
 
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goldsmith

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Hi
As i know , you can go through LT (Linear technology productions ) chips . I used many led drivers and current controller chips from that company .
However it would be nice if you could at least give us more specifications . Isn't it ?

Best wishes
 
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