AN2929

Testing the board

Doc ID 15333 Rev 2

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Figure 9.

Figure 10.

When the device is working in burst mode, a lower frequency ripple is present. In this mode

of operation the converter does not supply continuous power to its output. It alternates

periods when the power MOSFET is kept off and no power is processed by the converter,

and periods when the power MOSFET is switching and power flows towards the converter

output. Even if no load is present at the output of the converter, during no switching periods,

the output capacitors are discharged by their leakage currents and by the currents needed

to supply the circuitry of the feedback loop present at the secondary side. During the