You require a 5V power supply for most of the microcontrollers or development boards like Arduino, Raspberry Pi, PIC, and others and ARM chips. You can use a portable battery if you want to make your project mobile but if mobility is not an issue you have to power your device to the most readily available power source which is your wall socket. The AC power flowing in the wall socket can not be directly used by your project hence you will need an AC to DC converter module which will convert the AC power to the DC power to be supplied to the project. If you want a reliable, weight and sturdy solution that you can use to power the device, you can opt for Hi Link - HLK PM01L - 5V/3W Open Frame SMPS Module - AC to DC Converter which has a maximum power output of 3W which is more than enough to power the development boards requiring 5V power supply.
 
Specifications
Input Voltage: 100-240V AC
Input Frequency: 50-60Hz
Output Voltage: 5V
Output current: 600mA
Power: 3W
Output peak current: 1000mA
Maximum Input current: 0.2A
Efficiency: 70%
In-built short circuit and over-current protection
 
Additional Resources
Datasheet
 
Package Contents
 1× Hi Link - HLK PM01L - 5V/3W Open Frame SMPS Module - AC to DC Converter