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The output drivers are darlington transistors, not MOSFETs.
The circuit requires an AND logic function, OP amps aren't an option in this case and generally don't seem to serve a useful purpose in driving transistors. What do you want to achieve?
The output drivers are darlington transistors, not MOSFETs.
The circuit requires an AND logic function, OP amps aren't an option in this case and generally don't seem to serve a useful purpose in driving transistors. What do you want to achieve?
Yes, there are darlington transistors, but I want to use Mosfets. 7804 in this circuit is AND gate IC, but it can only provide 5.25V to Mosfet-gates that my be not enough to make them on fully. That is why I am asking about OP amps or any other option.
I want to use it for same purpose as shown in circuit e.g. unipolar stepper.
I am using L297 schematic as shown in first post. I tried transistor C828A (instead of 7408) to drive 4 mosfets (IRFZ44) as shown in following image described in this article:
BUT, after connecting unipolar stepper and turning on power supply (ATX), both SENSE resistors turns very much HOT and motor does not move.
I SOLVED it by connecting SENSOR resistor ground to power supply negative terminal with a thick wire. Previously, Sensor resistor ground was connected to circuit with a thin wire.
But, now L297 output (ABCD) keeps high and keeps all 4 mosfets on, so motor does not move.
If I disconnect motor then all L297 outputs work find.
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