Hello, I have this circuit in the figure. The GPIO send a signal to the MOSFET to control the LED. It’s a simple circuit, but it’s not working and I cannot figure out why. Maybe I need to choose another mosfet?
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trivia : http://www.everlight.com/file/ProductFile/67-31EP6-UY0500H-AM.pdfbut it’s not working
So, most likely there's something going on with the GPIO's .... I would disconnect the gates from the MCU's pins (but leaving the 10k pull-down resistors), and then test them by by manually connecting and disconnecting them to Vcc. If they work as planned, then definitely there's something going on with the MCU...They are not down to 0. Vg at LED1 is 0.04 V and Vg at LED2 is at 0.24 V
Good call... if he's working with an SMT device, then surely it's mounted on a makeshift PCB, and maybe its traces are short circuited at some point... that would explain the non-zero voltages at the gates.hi Gp,
Do you a photo of the project that you could post which shows the FET and LED.?
I’ve actually already been trying to manually pull the signal high or low on a breadboard and I’m still getting the same issue, so it’s not the MCU. What are some ramifications of overheating the mosfet during soldering? Maybe that caused an issue?Another thought that comes to mind, is that you might inadvertently be applying a PWM signal to the gates. Do you have an oscilloscope?
I actually have a prototype PCB that I’m using this on, but I cannot send pictures of it as it is proprietaryGood call... if he's working with an SMT device, then surely it's mounted on a makeshift PCB, and maybe its traces are short circuited at some point... that would explain the non-zero voltages at the gates.
No problem, we understand. My only advice would be for you to be meticulous and do a step by step check of all possible scenarios. And also, we'd love to hear about it when you finally solve it... we're all of a curious nature in this place.I actually have a prototype PCB that I’m using this on, but I cannot send pictures of it as it is proprietary
-- try 100kΩ or higher to gate from +7V +10V +14V -- while so log V.drain to GND voltages (keep LED at where it is +5V)manually pull ... same issue
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