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Solenoid PWM Control

Posted: Mon Oct 15, 2018 3:00 pm
by BenLewis
I'm considering using the RP for PWM control of a solenoid. The switching frequency is 50 Hz. The duty cycle must be variable from 0 % to 100 % in very small increments (0.004 ms). This requires an output clock rate of at least 250 kHz. The output of the RP will be connected to the gate of an N-Channel Mosfet (FQP30N06L). The fast analog output is more than capable of the required speed but is limited to just +/- 1 V. The slow digital outputs switch 3.3 V (which is ideal) but are limited to 100 kHz.

Is there a way to increase the voltage of the fast anlaog output? Or is there a way to increase the speed of the slow digital outputs? Or is there another solution?

Regards, Ben

Re: Solenoid PWM Control

Posted: Thu Oct 18, 2018 3:09 pm
by BenLewis
Does anybody know if it is possible to output a pulse train on one of the GPIO pins with a resolution on the pulse width of 4 microseconds or better?

Regards, Ben

Re: Solenoid PWM Control

Posted: Mon Oct 29, 2018 7:59 am
by amike88
Voltage on GPIO analog outputs can only be increased by some external amplifier, the maximum is 3V3.

Slow digital outputs can work very fast if they are controlled by FPGA PWM module, but this is not part of the official release implementation.