A regulated power supply can be built to transform high‑voltage alternating current (AC) into a stable direct current (DC). The conversion occurs in four stages: stepping the voltage, rectifying it, smoothing the ripple, and regulating the final output. Understanding the electrical relationships behind each stage is essential for designing a reliable supply.
Start with a step‑up or step‑down transformer to adjust the incoming AC voltage to the desired level. The transformer’s output is dictated by the turns ratio of its primary and secondary windings.
Connect a four‑diode bridge rectifier to the transformer output. The bridge converts the alternating positive and negative cycles into a unidirectional pulsed DC voltage, as pairs of diodes conduct alternately.
Use a reservoir capacitor to reduce the ripple in the pulsed DC. The capacitor charges during voltage peaks and discharges during troughs, producing a near‑constant voltage with minimal fluctuation.
Attach a voltage regulator that sets the final DC level. The regulator’s input voltage must exceed the target output by a few volts to accommodate ripple and voltage drop across the bridge.
Multiply the AC root‑mean‑square (RMS) value by 1.414 (the square root of two) to find the peak voltage. For example, 10 V RMS becomes 14 V peak.
Divide the peak voltage by 1.414 to estimate the rectified DC voltage. A 14 V peak yields roughly 10 V DC.
The actual DC output will be slightly lower than the RMS value due to diode forward drop, transformer losses, and residual ripple. Proper component selection and smoothing will minimize this discrepancy.
AC voltage is reported as an RMS value (~71 % of peak). Converting to DC involves stepping, rectifying, smoothing, and regulating. The final DC voltage depends on component losses and ripple suppression.
Working with electrical power carries inherent risks. Follow proper safety protocols to prevent injury or fatality.
