These ICs work together in an active clamp flyback converter topology:
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Lots of design examples are provided in the ‘design examples’ of the InnoSwitch page:
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DCM example:
DER-979 - 100 W In-Wall USB Outlet with Selectable Output Voltage
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For DCM, tHLDLis a function of fet capacitance and leakage + magnetizing inductance of transformer
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If constant current regulation is not required, the ISENSE pin must be tied to SECONDARY GROUND pin
Component Selection
Clamp Capacitor
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