1. Why is optocoupler biasing critical in isolated SMPS feedback loops?
Answer: Optocoupler biasing directly affects loop linearity, transient response, and long-term reliability. Improper biasing leads to saturation, sluggish feedback, or instability.
2. What does it mean to “bias an optocoupler” properly?
Answer: Biasing of an optocoupler means driving the LED within the optimal forward current range (typically 1–10 mA) and ensuring the phototransistor operates in its linear region—not saturated or cutoff.
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Understanding Optocoupler Biasing for Stable Isolated SMPS Feedback
Compensation Network Design in Isolated SMPS Feedback Loops