I bought logic level n channel mosfets, the irlz 34 and 44n, to be specific and want to control a 5volt lcd shield on the high side with and arduino pro mini which can output 3.3v on its pins for the gate. It seems that it doesnt work as planned until i use the low side switch configuratio but i need to control the high side. Is there an efficient way to do it?

I appreciate any attempt to help and thanks in regards

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    \$\begingroup\$ You need a high-side gate driver... or just switch the low side. \$\endgroup\$ – Hearth Feb 18 at 15:53
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    \$\begingroup\$ Please draw a schematic and include that in your question. This site as a built-in schematic editor. Click the button that looks like a small circuit. \$\endgroup\$ – jwh20 Feb 18 at 16:21
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    \$\begingroup\$ You need the gate 2v higher than the source/drain. how is the project powered? If 5v is as high as you got, it's complicated. If you have 12v avail, we might be able to work something out. One neat trick i've done is wire 4 red LEDs in series, glue them together side-by-side, then glue a super bright white LED shining into the reds. When the white is lit by the MCU, it produces about 4-6 volts across the reds, which you can connect to gate and source, along with a 1m resistor. \$\endgroup\$ – dandavis Feb 18 at 16:41