Influence of a Control Loop by an Output Filter

Output filters are often used for noise suppression, which may have an influence on the control loop. To prevent output power losses, it may be necessary to compensate the control loop. No matter what switching regulator topology is used, as a result of the parasitic series resistor ESR, and the parasitic inductance ESL, of the output capacitor, the output current causes an undesired residual ripple. Download the complete Application Note, ANP006, at www.we-online.com/appnotes or click here.

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