5V-1A power supply design

Today, we are going to design and construct a 5V-1A regulated power supply from scratch. The following are to be taken into consideration in order to accomplish an amazing end result.

The output voltage, V_out=5V
The input voltage, Vin=240V
Also have a conception of the general idea, kind of components to be used.

Functioning
Normally, our device (PS to be constructed) will receive 240V from ENEO, then through a protective circuit comprised of a fuse block before stepping down the voltage through a step-down transformer and then rectifies it by means of a bridge rectifier. A filtering circuit then filters by eliminating the ripples as well as the electric noise before it is being regulated using an IC regulator to a fixed output voltage to be used by any 5V-system. All these rise up to a block diagram shown below

Block diagram of 5v-1a regulated power supply

The regulation block

This block consist of a fixed IC regulator whose datasheet could be found here. This block makes sure only a fixed output voltage is delivered at its output for usage.

The fuse block
The block consist only of a fuse.
V_eneo = 240V and I_seff= 1.8A
→Fuse (V = 240V and I= 1.8A)
The rectification block

This block consist only of diodes having a forward current each of
I_F = 0.9I_out
V_RRM = 2.2V_seff V_seff = transformers output voltage
V_seff= V_cmin + 2V_d V_d = 0.7V
→ V_seff = 7.5 + 1.4 = 8.9V
→ V_seff = 8.9V
→ V_RRM = 2.2 x 8.9
→ V_RRM = 19.8V
For security reasons, V_RRM = 19.8V + 19.8V/2
→ V_RRM = 29.7V,
The filtering block
It comprises a polarized capacitor that is capable of reducing the ripples produced by the AC supply