In Reply to: Resistor dissipation Question posted by timp on September 15, 2012 at 20:26:39:
An important fact that nobody has mentioned... the RMS current through this resistor is considerably higher than the total DC current! The current waveform here is not a sine wave - it has a higher peak value due to the charging current for C1. Another to way to look at it - the resistor carries the DC output current PLUS the ripple current in the capacitor.
PSUD will have an RMS value for the resistor in the table - THIS is the figure you must use to calculate dissipation. It's higher than you think...
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Follow Ups
- RE: Resistor dissipation Question - Tom Bavis 09:07:04 09/17/12 (2)
- RE: Resistor dissipation Question - timp 10:00:40 09/17/12 (1)
- RE: Resistor dissipation Question - drlowmu 10:19:15 09/17/12 (0)