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How to get 30 volts as Vout from LYT 1402-1604 (LYTSwitch-1 Family)

Posted by: on 10/29/2021

Hi there,

We have used  LYT 1402-1604 (LYTSwitch-1 Family) to get the output voltage as 30 volt. We have use High-Side Buck circuit on figure 1a. of data sheet.

If the value of R7 is kept 402k ohm (as per figure 5 on page no 3, in Rev.B 07/16), we get Vout over 100 volt dc.

And if I choose R7 value to be 100k ohm, I get Vout as 75 volt DC constant.

Why when I chose the right value of R7, I do not get the expected voltage.

 Also, how can I get 30 volt as Vout.





Submitted by PI-Salt on 11/09/2021

Hi Niraj,


Thank you for showing interest in Power Integrations and its products.

According to the datasheet, resistor R7 is set to a fixed value of 402 kohms and R4 will determine the overvoltage limit. 

R4 can be calculated as follows; R4 = 2V x R7 / (Vout - 2V)

For a 30V design, R4 is 28.7kohms


Thank you.


Please let us know if you have further questions.