Hey guys,
currently working on my diploma for school. Trying to build a guitar playing robot. So far so good, but when designing the circuit which controls the pushing magnet (don't know how it's correctly called in english, datasheet attached, couldn't find an english one) I am running into problems.
I got a PCB with 10 Inputs which I get from an myRIO, which outputs 3,3V to control each MOSFET. When the MOSFETS gets the 3.3V it should let the current flow, and if not it should stop it. At the end i connected my 2 pushing magnets which should presss the strings on the guitar.
When I tested each lane everything worked fine except 2 lanes. I began to measure and test if there was a shortvut womewhere, but I couldn't find one. So I replaced a MOSFET and tried again. And look, it worked now.
But then I realised that another lane had stopped working. Maybe I destroyed it in the measuring process? I don't quite know.
Hope you can more or less follow me here. I attached my schematic.
The first time I tested I had 120 Ohm Resistor on the Gate.
Later I also tried 620 Ohm and 3k3 Ohm Resistors at the Gate. It worked all the time. The resistor shouldn't be that important anyway due to me just driving the thing with an myRIO which can be compares to something like an Arduino and I don't have huge Voltages on the Gate.
The pushing magnet is powered by 24V and usually takes about 300mA. (for more view the datasheet)
Is there a problem with my circuit? Is the Resistor wrong? Any recommendation?
Thank you very much in advance,
Hope you can help me. That's the first time I am working with MOSFETs
currently working on my diploma for school. Trying to build a guitar playing robot. So far so good, but when designing the circuit which controls the pushing magnet (don't know how it's correctly called in english, datasheet attached, couldn't find an english one) I am running into problems.
I got a PCB with 10 Inputs which I get from an myRIO, which outputs 3,3V to control each MOSFET. When the MOSFETS gets the 3.3V it should let the current flow, and if not it should stop it. At the end i connected my 2 pushing magnets which should presss the strings on the guitar.
When I tested each lane everything worked fine except 2 lanes. I began to measure and test if there was a shortvut womewhere, but I couldn't find one. So I replaced a MOSFET and tried again. And look, it worked now.
But then I realised that another lane had stopped working. Maybe I destroyed it in the measuring process? I don't quite know.
Hope you can more or less follow me here. I attached my schematic.
The first time I tested I had 120 Ohm Resistor on the Gate.
Later I also tried 620 Ohm and 3k3 Ohm Resistors at the Gate. It worked all the time. The resistor shouldn't be that important anyway due to me just driving the thing with an myRIO which can be compares to something like an Arduino and I don't have huge Voltages on the Gate.
The pushing magnet is powered by 24V and usually takes about 300mA. (for more view the datasheet)
Is there a problem with my circuit? Is the Resistor wrong? Any recommendation?
Thank you very much in advance,
Hope you can help me. That's the first time I am working with MOSFETs
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