I need to power the Raspberry PI4 from my embedded system so i used a DC/DC regulator(https://www.sparkfun.com/datasheets/Components/LM7805.pdf) from a bipolar power supply composed of two 9v batteries the DC/DC regulator gives as output 5V and 1A but for the raspberry PI4 I need 5V 3A.Can anyone propose for me a solution to amplify the current or its ok to give the raspberry PI 1A as input current.I am new in this field.Thank you for the help.
Electronic – Current amplification for Raspberry PI4 powering
amplifiercurrentpower supplyraspberry pi
Best Answer
The common 9 volt rectangular batteries cannot supply 3 Amps - they are designed for low current applications - I think even 100 mA is a bit much for them.
The LM7805 is a linear regulator and will waste over a third of the power you draw from the battery as heat.
Four AA cells and a DC-DC converter (switching power supply) may work, but 3 Amps is really too much for an AA cell - C or D cells would be better.