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Buckboost led driver with low side FET

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grizedale

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Hello,

I am looking for a buckboost led driver for vin=10v, vout = ~48V, 350mA.

Obviously, the sense resistor in series with the leds is not referenced to ground, and so a high side current sense amplifier is needed.....but no ICs seem to offer this.

I dont want one that simply senses the fet current because that is inaccurate as it is not the led current and as led vf's vary, i would get inaccurate led current

Do you know of an ic?
 
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A boost converter may do what you want. It's not too different from the buck-boost. It adds the supply voltage to the coil kick current.

You can re-arrange either type (boost or buck-boost) so as to place the mosfet (or transistor) closest to either the positive supply or the negative supply. In some cases you might rather use a P-mos instead of N-mos.
 

Dear grizedale
Hi
What do you mean by that ?
but no ICs seem to offer this.
Click to expand...
i'm confused that what do you want to do exactly ? ( tell me more explanation , please , thus i can help you . )
Best Wishes
Goldsmith
 

thanks but my kindest and considerate friend, i explain to you the words "buckboost led driver with low side FET and LEDs referenced to the input voltage"

....and really, that can only mean one thing, if it does not mean anything to you , then i would say that you are probably not going to be able to comment on this.

I am humbled by your responding to me and taking your time to consider me, but i say to you my friend, that if my basic explanation means nothing to you , then thanks for trying, really, thanks.
 

Your question really isn't very clear grizedale.... a normal buckboost converter does have a ground referenced load (but of negative polarity). Are you referring to a Vin referenced converter?
 

yes.

"buckboost led driver with low side FET and LEDs referenced to the input voltage"
 

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