I’m trying to build a 5V output @ 200mA. I have a full wave bridge rectifier attached to a transformer with a capacitor reservoir of 100uF, using a LM7805 voltage regulator and with a 0.1uF cap as well. To get the 200mA that I needed I used ohms law to find I needed 25ohms (5V/0.2A=25ohms.) But that power will burn out my resistor so I thought that I should use 4x 1/4W 100ohm resistors in parallel to achieve the same result. When I turned on my circuit, my voltage regulator became super hot and the voltage I recorded was lower then 5V (3.8V).
I've attached the schematic I drew to show how I wired it. Can you tell me what I have done wrong ? Sorry for the crappy drawing in advance.