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I am using the raspberry pi to generate a PWM signal to feed the servo motor. The output voltage (Max) from a Rpi GPIO is 3.3V whereas I need it to be 5V for my specific application.
So I am thinking of using a Voltage amplifier, I have two choices:

1)A non-inverting amplifier like this:
enter image description here Where Gain Av=Rf+R1/R1

2)A Transistor voltage amplifier something Like this:
enter image description here

Questions:

1)what would be the best choice?
2)considering the PWM frequency to be somewhere from 20-200KHz, Which one of those will provide the better output response?

Thankyou.

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  • \$\begingroup\$ It depends what you're driving with the PWM signal. More information, please.... \$\endgroup\$
    – Finbarr
    Commented Apr 5, 2017 at 10:32
  • \$\begingroup\$ @Finbarr it a servomotor drive so current is not an issue . \$\endgroup\$
    – Mr.Sky
    Commented Apr 5, 2017 at 10:34
  • \$\begingroup\$ But does it even need to be driven right up to 5V or is 3.3V sufficiently above its high input voltage for you to avoid amplifying it at all? \$\endgroup\$
    – Finbarr
    Commented Apr 5, 2017 at 10:38
  • \$\begingroup\$ Which servo motor drive? \$\endgroup\$
    – Bruce Abbott
    Commented Apr 5, 2017 at 10:38
  • \$\begingroup\$ @Finbarr high input Vtg is about 4.8V-5.5V so we need to amplify the voltage. \$\endgroup\$
    – Mr.Sky
    Commented Apr 5, 2017 at 10:39

1 Answer 1

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Quite a few ways to do it. The simplest would be a transistor plus a collector resistor to the 5v rail. You can also use logic gates powered from 5v. Optocouplers, dedicated drivers, or even just a resistor or a diode. ... Or nothing.

All depends on the devices involved.

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