I'm creating an ignition circuit with an NE555 timer--monostable circuit--in order to manipulate the spark igniton circuit to automatically shut off after a short amount of time. The load from the ignition coil causes the timer to burn out. So, I've put a HV FET between the output of the timer and the load to prevent the timer from burning. I've attached a schematic of the circuit to show you. Disregard the timer on the far left for now.
My question is with the diode (D1) between the FET (MN1 HV) and the ignition coil. It is supposed to be a high current power diode to prevent the FET from damaging. I'm testing the circuit with a simple LED to make sure the circuit works. However, when I place a diode (any diode) between the FET and the LED, the LED doesn't emit light like it should. Why is this the case? Are there any suggestions? When I test the circuit without a diode between the FET and the LED, the LED emits light for a second after I hit the switch, as I want it to.
So, is there an issue with how I'm connecting the diode to the circuit? Is there any special way to connect it?
Thank you.
My question is with the diode (D1) between the FET (MN1 HV) and the ignition coil. It is supposed to be a high current power diode to prevent the FET from damaging. I'm testing the circuit with a simple LED to make sure the circuit works. However, when I place a diode (any diode) between the FET and the LED, the LED doesn't emit light like it should. Why is this the case? Are there any suggestions? When I test the circuit without a diode between the FET and the LED, the LED emits light for a second after I hit the switch, as I want it to.
So, is there an issue with how I'm connecting the diode to the circuit? Is there any special way to connect it?
Thank you.
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