Electronic – Mosfet Motor Drive amplifying duty cycle of PWM

dc motorpwm

I am receiving PWM signal at 7.8V from a given controller, with which we need to control the speed of a DC motor at 18 V. I implemented the following circuit for this.
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However, the output to motor signal (blue) is not following the original PWM (yellow) and duty cycle is increased by 50%. What could be the culprit. I dont think it is the awkward taper off on the downleg of the input signal enter image description here.

What could be a remedy?

How about this solution?

How to reduce MOSFET turn-off delay

Best Answer

Thanks to the comments/suggestions provided here, we found the solution. We modeled the circuit in Proteus and were able to recreate the output signal. Proteus recreation of Original Circuit Then, as suggested by @G36 the 10k ohm resistor was reduced to 820 ohm, and few minor modifications. Modified Circuit Simulation environment predicted better results: Simulated output of modified circuit On oscilloscope too results were verified as true to form. Actual output of modified circuit

Thanks to all contributors!

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