Switch Mode Power Supply

Switch Mode Power Supply

Hello there, this project is to showcase how you could go around building your Switch mode power supply or in short “SMPS “

The reason behind building this project is to limit using my usage of these little 9-volt income draining suckers in powering my circuit 👨‍🦯

More so to avoid looking for selective voltage level when in need of a power supply. I'll assume we all know the relevance of power electronics in any circuit and its importance, The power supply being built is capable of delivering 0v - 12v at 700mA to 1amp depending on current drawn by the load... Who needs 0v anyways 😅... I'll go over the build in 3 steps...but first off let's go over the components used

Components Used -Purpose

12v Step Down transformer (1) –Stepping down AC voltage from main(220v) to desired output

Switch (1) - Power ON /OFF

Diodes 1N4007 (4) – Rectification dudes

1000uf /25v Capacitor (Electrolytic) (1) --- 1st stage filtering

10uf/25v Non-PolarElectrolytic capacitor (1) --- 1st stage filtering

Resistor 220 ohm (1) -- Current limiting Resistor

LED 1 -- ON Indicator Light

LM7812, LM7809, LM7805 (1 each) - Voltage regulators; outputs predefined voltage level at fixed current of 1amp

470uf /16v (3) - Filtering and delivering of a Regulated DC output supply

104 / (0.1uf) (3) Film capacitor - Filtering and delivering of a Regulated DC output supply

Terminal Block (3)

10k potentiometer (1)

BUILD

Connections

1. The terminals from the secondary side of the transformer is connected to the Switch then to the Diodes (D1 to D4) (1N4007) where rectification begins; the arrangement of the diode is in a unique manner for rectification to take place. Ensure you follow the proper polarity for the Diodes.

2. From the Diodes It goes on further to the Capacitors (1000uf/25v and 10uf/25v) which are connected in parallel to the diodes then to the 220ohm resistor which limits the current going to the LED that serves as a visual indicator. (Also take note of the Electrolytic capacitor polarity).

3. The Inputs from the Voltage regulators (U1 to U3) are then connected in parallel to the capacitor (C2) while the Ground pins on the Voltage regulator are connected to the Ground line and the Output of the Voltage Regulators is connected in parallel to two more capacitors (470uf electrolytic capacitors and 104 film capacitors and then to the Terminal Block connectors….(”This stage can be repeated/cascaded along with other voltage regulators to get required voltage level for any voltage regulator ”)

For the 5V regulator (LM7805) after the filtering and regulation at (C7&C8), We also needed lower voltage levels like 3.3v, after repeating the 3rd step a 100k potentiometer was connected to achieve that.

Prototype

FINALBUILD

TESTING

Yeah...so there you have it, no more battery voltage depletion, with this article you should be able to pull off your stable SMPS successfully. Thanks a lot for coming by, and I hope you enjoyed the read, Kindly leave some ‘appreciation’ and check out my other post Thanks 🙂