Arduino nano mosfet problems

Other Hardware General Electronics
1

I have a IRLZ44N mosfet being controlled by a nano. I’m using the mosfet to ground a AC (1.5V) to ground in pulses not constantly ground it.

I have the wiring as follows:
Pin 6 from nano to a 220 resistor to now a diode(explanation will be later) to GATE.

Drain to AC wire

Source to ground
Pull down(tried 10k, 4.7k, nothing) from gate to ground

First discovery found the drain was actually grounding through the GATE when the mosfet was triggered low. Took out the pull down, still grounding through GATE added the diode fixed that issue.

Now even when triggered low it will ground through source, no matter what I do.

I cannot add a resistor in between source and ground as it NEEDS to see complete ground to effectively prevent operation.(I’ve tried this)

Has anybody else had a mosfet “bleed” through? What did you do to remedy it?

Yes I have tried other mosfets. Thanks all

2

MOSFETS only work as a switch for DC.

image
image193×200 4.82 KB

Notice the diode. It will conduct your AC when the source is positive and the drain is negative.

3

Thank you that makes perfect sense! Is there any component I could use instead?

Could I try the “totem pole” method?

4

Do you know what that means?

How fast do you need these "pulses" to be?

5

Fairly new to this side of electronics. I don’t know exactly what that means I would have to read more, came across this during my reading last night.

Currently have it pulsed at 100Hz. Don’t know what they will be in the end. I need to see what will work and what will not for my application.

6

Basically you do need two MOSFETS back to back so when they are off, current is blocked in both directions. However, working with small voltages, 1.5V AC can make a circuit design challenging.

7

I’m going to give it a shot tonight and see what happens, I’ll report back.

8

Give what a shot?

9

I thought a triac would work for AC but probably not for the low 1.5V. Use a relay.
OOps, a relay wouldn't work pulsed a 100 Hz.

10

I have a nitrous solenoid/ssr I’m gonna try tonight

11

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