Hi guys.
I am making a small integrated amp for my bedroom.
I am integrating both fm radio and Bluetooth into the unit.
Both the fm radio board and the Bluetooth board require 5vdc.
Ideally these boards would not be powered while not selected as a source via a relay input selector board.
Is there a reason not to switch the output of a 5vdc psu with relays so that the Bluetooth/radio boards are not powered when not required?
I am making a small integrated amp for my bedroom.
I am integrating both fm radio and Bluetooth into the unit.
Both the fm radio board and the Bluetooth board require 5vdc.
Ideally these boards would not be powered while not selected as a source via a relay input selector board.
Is there a reason not to switch the output of a 5vdc psu with relays so that the Bluetooth/radio boards are not powered when not required?
Almost always. But to be sure put a 1,000 ohm or so resistor across the power supply so there is always a load. The power dissipated is the voltage squared divided by the resistance. So for 5 volts at 1,000 ohms it would be 5•5/1000 or 25 milliwatts. Use a resistor at least twice that so a normal 1/4 watt resißtpr should be fine.
You probably can use any value from 220 ohms to 1,000 ohms.
You probably can use any value from 220 ohms to 1,000 ohms.