powering a mini pump with a GPIO pin

hi everyone. My raspberry GPIO pin generate 3v 40ma and i am wondring if i can use a booster step up to power up a mini pump (12v 0.5a) using the GPIO pin with this booster step up without using the relay and a new outside power source ? if its impossible can anybody tell me if there is a way to power my mini pump with the GPIO pin without using an other power outside source ?

No, you need an external power source.

3V@40mA = 120mW

12V@0.5A = 6W

6W > 120mW

Stepping up 120mW to 6W without an external power source would be a perpetual motion machine.

No, you need an outside power source - you can't create energy from nothing.

The I/O pin can only supply 0.12W the pump needs 6W (and probably much more to start it).

A bypass trick is If your Raspberry Pi source can supply that current and the voltage is made with a voltage multiplicator, it can work, but you have not clearly stated the requirements. Plus it will be harder with more components, its better to put an external source with an NMOS transistor and turn on/off.

thanks guys for the answer

abouabdelmajid said:

thanks guys for the answer

Click to expand...

You can have a single power source if you...

Use a 12v power supply to power your pump,
Split off (with a USB car charger) the 5v you need for the raspberry pi power
Add a "relay shield" that simply sets on top of the RPi and plugs into the GPIO pins.

Use a 12v supply with 2.5 amps minimum.

You'll have to splice the 12v USB charger to your 12v supply - many options how to do this depending on how well you solder or what you are willing to pay for various connectors and adapter cables.