I'm just checking a few things out before using it (I have no prior experience with this type of device). I connect 12v to the input, enable A and B output with jumpers.
I measure voltage on output and this is approx 12v out when I power the input pins. What confuses me is that the output voltage is not zero but 0.34v when the input pins are not enabled. My expectations are that it should be zero...
Is there something wrong with the device, my expectations or something else?
There will be a small amount of leakage current through the l298n when it is turned off, so if the only thing connected to the output is your voltmeter, it is not surprising that it registers a small voltage. It will read much closer to zero when you connect a motor to the output. OTOH it will read somewhat less than 12v when you command the l298n to turn the motor on.
Since the device has darlington output stages it will have quite a large leakage current
(compared to single transistor output stage), but still effectively zero when we talk
about driving a motor.
The chip designers didn't care about the unladen output voltage of a motor driver,
its not a useful parameter, you might even be the first to try measuring it!
