Looking for electronic switching device ideas
- Thread starter Dr.Jeff
- Start date
Dr.Jeff
True Classic
No scope.
The MOSFET was connected as shown in the schematic earlier. No idea what that means in terms of the gate being grounded; perhaps you can tell by looking at that schematic?
With the MOSFET in place I got a constant signal output to the injector, but no pulsing. So I removed the MOSFET just to see what would happen - hoping that might narrow down where the problem was. But I think that fried the 555 because there was no signal at all. The spec sheet for the 555 says it is capable of 200mA and a single injector is 2-3 A.
The MOSFET was connected as shown in the schematic earlier. No idea what that means in terms of the gate being grounded; perhaps you can tell by looking at that schematic?
With the MOSFET in place I got a constant signal output to the injector, but no pulsing. So I removed the MOSFET just to see what would happen - hoping that might narrow down where the problem was. But I think that fried the 555 because there was no signal at all. The spec sheet for the 555 says it is capable of 200mA and a single injector is 2-3 A.
dllubin
Don
If you tie the gate to the source, the MOSFET should stop conducting from the drain to source. If it does not, it is bad. In the circuit you have, the 555 output should not be supplying much current. Some of the current will take the path through the resistors and some will go to charging the gate capacitance when the 555 output changes state.