A bridge rectifier with four silicon diodes gets its input from a transformer that gives 18 V rms…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A bridge rectifier with four silicon diodes gets its input from a transformer that gives V rms at Hz. Each conducting diode drops V. Find the peak voltage of the transformer, the peak of the output, the direct voltage of the output and the ripple frequency. Last, find the greatest reverse voltage across one of the diodes that are off. A conducting diode in the loop takes V of the transformer voltage, and the rest is across the diode that is off.
Need a reminder? The key ideaShow
For an ideal half-wave rectifier, , and the ripple frequency is . For an ideal full-wave rectifier, , and the ripple frequency is . A capacitor filter gives and . A silicon diode drops V when it conducts.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The transformer peak. V.
Step 2. The peak of the output. Two diodes conduct, so V.
Step 3. The direct voltage. V.
Step 4. The ripple frequency. Hz.
Step 5. The reverse voltage. A diode that is off has the transformer voltage across it, less the drop of one conducting diode in the same loop. So it is V.
Answer: V, V, V, Hz and V.
Watch out. A diode for this bridge needs a rating above V, so a rating of V or more is chosen. A centre-tap rectifier from the same transformer would need twice that rating for each diode.
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