Hello Everyone,
I have a 24V power supply (PSU from now on) with a load attached to it, inside my PC that I want to either turn on automatically when I switch on my PC, or to manually turn it on even if the PC is switched off. I will be using the PC 5V output to detect when the PC is switched on.
I will use a 5V relay between the 220V mains and the 24V PSU, but I need a very small 5V PSU that would be able to keep the relay on. The relay will be requiring around 100mA at most (generally the requirement is around 70mA).
Basically, I am trying to achieve the following (pseudo-)schematic:
The 5V PSU does not require too much attention to filtering, regulation, precision, ect. As long as it keeps the relay turned on without flickering, it's good enough for me (it should keep the voltage between 4.5V and 5.5V though). And it will also be used for this only, single purpose; not even an extra LED will be attached to it.
And obviously, I am posting because I need help in designing one that use as few, small and inexpensive components as possible.
Do you have any suggestions?
I have a 24V power supply (PSU from now on) with a load attached to it, inside my PC that I want to either turn on automatically when I switch on my PC, or to manually turn it on even if the PC is switched off. I will be using the PC 5V output to detect when the PC is switched on.
I will use a 5V relay between the 220V mains and the 24V PSU, but I need a very small 5V PSU that would be able to keep the relay on. The relay will be requiring around 100mA at most (generally the requirement is around 70mA).
Basically, I am trying to achieve the following (pseudo-)schematic:
The 5V PSU does not require too much attention to filtering, regulation, precision, ect. As long as it keeps the relay turned on without flickering, it's good enough for me (it should keep the voltage between 4.5V and 5.5V though). And it will also be used for this only, single purpose; not even an extra LED will be attached to it.
And obviously, I am posting because I need help in designing one that use as few, small and inexpensive components as possible.
Do you have any suggestions?