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Electronics => Projects, Designs, and Technical Stuff => Topic started by: tipo1000 on April 02, 2019, 07:02:07 am

Title: How to drive NFET with current sink (LP5569)?
Post by: tipo1000 on April 02, 2019, 07:02:07 am

I have a circuit (pic attached) where LP55231 is driving NFET and the load is a LED. It's working fine.

Now I need to switch LP55231 to LP5569. The difference is that LP55231 PWM output is current source and LP5569 PWM output is current sink. (LP55231 and LP5569 functional block diagrams attached.)

How do I need to change the circuit to get it work with LP5569?
I tried to figure it out with LTspice, but couldn't get it to work.

Thanks,
Tipo

Title: Re: How to drive NFET with current sink (LP5569)?
Post by: Wimberleytech on April 02, 2019, 02:48:18 pm

Just use a complementary version.