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How do I wire a LTC3780 to my arduino and display? Answered

I'm re-purposing an old ATX psu into a variable bench psu. The current project has LM2956's however they're faulty, I can only see 11.78V max instead of 29+V. The other down side to these modules is the lack of current control. The project also has an arduino Mega handling acs712 hall current effect sensors and Voltage dividers for my 3.3v 5v 12v terminals and two LDC dispays 16x2 and 16x4.

So I was wondering assuming I keep the basic design of the psu can i replace the LM2956s for a single LTC3780, How can I wire the LTC3780 to the arduino and allow me to see the current change. 

Thanx in advance.


How can a BUCK converter take any line from a ATX PSU and make it HIGHER than the original rail ?

Show me a datasheet, its got a TI part number, but TIs website doesn't show any. There is an LM2596 though, which is a buck converter.

That component is irrelevant as I want to replace it and install the LTC module.

Your criticism of the LM2956 is "They're faulty", my point is if your stupid enough to use a component designed for buck, not boost, its not surprising really.

Designing around a part as sophisticated as a LTC3780 is not trivial.

Current is measured with your hall sensors, they're noisy as hell, and not particularly linear, but they will work for a PSU.

They are meant to be boost, I clearly stated that.

I don't understand what you're talking about "not trivial"

And if I could use the hall current sensors regardless of noise, I wouldn't be hear asking for help. Reason is, Hall current sensors work by measuring the current flowing through, however with the LTC3780 you can change current levels before the current starts to flow. So How do i display the change in current thr LTC to the LCD.

You can clearly state what you like, the datasheet for the LM2596, which is all I can find, there is no sign of a LM2956 Boost converter, says its a buck converter.

If you can't tell the difference, then you can't design around an LTC3780 buck/boost.

And I can see no signs on the LTC3780 of a remote set pin. Show me your circuit diagram. The 3780 is a current MODE power supply, but its regulation seems to be from a resistor network across the output cap, which makes it a constant voltage supply.

sorry for long reply. I clearly understood what you meant, its just i ordered one of them LM2956's and they when up all the way to 29V.. I remember clearly as i tested a 24v circuit with it as i didnt have a PSU, hence why i tried to make 1.
so who is stupid here?

Why do you want to connect a buck converter to Arduino?
If you want to check the current you measure the voltage drop on a shut.

My lcd is connected to the arduino. Thats how i get my voltage and current readings on the 3.3 , 5 , 12 v lines.