MP174 – NON-ISOLATED OFF-LINE REGULATOR

MP174 Rev. 1.01

www.MonolithicPower.com

13

8/18/2016

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Open-Loop Detection

and a re-start cycle will begin. During Soft-Start,

the open loop detection is blanked.

Leading-Edge Blanking

An internal leading-edge blanking (LEB) unit

avoids premature switching pulse termination

due to turn on spike. Turn on spike is caused by

parasitic capacitance and reverse recovery of

freewheeling diode. During the blanking time, the

current comparator is disabled and can not turn

off the external MOSFET. Figure 5shows the

leading-edge blanking.

350ns

t

Figure 5: Leading-Edge Blanking