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Innoswitch3-EP input voltage range

Posted by: mat117 on Thu, 04/29/2021

Hello, i was wondering what is the minumum input startup voltage of Innoswitch3-EP controller, because i can't find anything on datasheet. I'm speaking about the voltage to apply on startup to get the controller to work. 

Thanks in advance

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Submitted by PI-Spark on Tue, 05/04/2021

Hi mat117,

Thank you for using Power Integrations products.

InnoSwitch3 has a voltage monitor pin (V) for setting the input undervoltage and overvoltage protection of the power supply.

V-pin is typically connected into either the DC side or the AC side of the bridge rectifier with two high-value resistors.

When connected to the rectified DC voltage, a 3.8MOhm total resistance is commonly selected for universal input range designs.

The resulting current into the V-pin must exceed the brown-in threshold (IUV+ in the datasheet) for the controller to start switching.

Therefore, the minimum start-up voltage is determined by IUV+ and the V-pin total resistance used.