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LM5069: LM5069 issue

Part Number: LM5069

Hi,

I need your help about the LM5069MM-2/NOPB. The goal of the application is the following :

The productX have to supply the productY with 48V and 2 A. If the power is upper than 90 W, the LM5069 will shutdown the output power so the productY will shutdown. 

I have downloaded the calculator from your website. You will find it filled with the application. 

 

This is the schematic of productX :

The VIN pin(second image) is connected to C25 capacitor (first image). 

 

Note :

-diode D9 is not soldered so the LM5069 circuit is isolated from the rest of the product. The output voltage is between the Gate and AGND_BNC. 

-Following components soldered are : R76 = 24 mOhm, C62(Ctimer) = 47 nF, R75(RPWR) = 267 kOhm 

-Rest of components are the same as schematic so C73, R78, R21, R55, R74, R39

 

If the I connect nothing to productX, the output voltage between the gate and GND is 48 V. If I connect a productY the productX, the output voltage is 0 V. 

I tryed to connect a pure resistive load from 15 W to 90W to productX but there was 0V too. 

 

I hope you can help me, thank you for any help.

Regards,

Pierre