POWER SUPPLY (STABLE) SIMPLE ELECTRONIC PROJECT W/ SCHEMATIC DIAGRAM

Here is a simple Power Supply for your electronics project.

Circuit description: aC mains 230V aC is down converted to 15V aC by the step-down transformer X1, the secondary winding of which can support a current of 2 amperes. a bridge rectifier converts
the aC to pulsating DC with a peak voltage level of 21V (15x1.4142). lED1 lights up to indicate
availability of output from the rectifier. The 2.2 kilo-ohm resistor R1 limits the current through
lED1 to a value below 10ma (milli-ampere). The output from bridge rectifier is smoothed by 470μF capacitor C1. C2 is used for bypassing high frequency ripple.

Schematic diagram of power supply.

PARTS LIST

Semiconductors

iC1 - lM317T - 1.5a adjustable

regulator

D1-D9 - 1N4007 - rectifier diode

lED1 - 5mm - red lED

Resistors

R1 - 2.2 kilo-ohm - 0.25W, 1% MFR

R2 - 220-ohm - 0.25W, 1% MFR

R3 - 100-ohm - 0.25W, 1% MFR

R4 - 1.8 kilo-ohm - 0.25W, 1% MFR

R5 - 4.7 kilo-ohm - 0.25W, 1% MFR

R6 - 1.5 kilo-ohm - 0.25W, 1% MFR

R7 - 1 kilo-ohm - 0.25W, 1% MFR

R8 - 390-ohm - 0.25W, 1% MFR

Capacitors

C1 - 470μF, 63V electrolytic

C2 - 0.1μF ceramic disk

C3 - 10μF, 25V electrolytic

Miscellaneous

X1 - 230V aC primary to 15V aC, 2a

secondary transformer

S1 - Switch toggle, SpST

F1 - Fuse cartridge, 2a (with holder)

S2 - Switch rotary, single-pole 5-way

(in lieu Dip switch 6-way)

- heatsink

- Box for mounting hardware and

pCB

- lED holder

- Tag blocks for input

- Screwable binding posts for output

connection

- Screws with nuts and washers

- insulated spacers for mounting pCB