Reseting problem i LYT 5228D_Line Sense Pin_Reg

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Hi,
we are using LYT5228D IC for our LED lighting application. We are using the recommended 2.4Mohm+2Mohm resistors at the line sensing pin of the IC. It is denoted that it can support a input voltage threshold of 260V (90-308V) as given in its datasheet. But as we have tested the circuit with the load whenever the input voltage increases beyond 220V the IC resets the load and it powers the load after some seconds. The changes we have done in our circuit are changing the values for resistors R1 and R2 (R1 changed from 732Kohm to 1Mohm : R2 changed from 56.2kohm to 47Kohm).SO
i)can i get any reference(study material) regarding the value of resistors R1,R2,R4 and R5 .How to calculate the resistors used there?
ii)can someone give us a solution regarding the resetting problem?

I have attached our circuit recommended from PI integrations .

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LYT_Driver_Ckt.jpg92.97 KB

i cannot understand what you are asking. But if the question is regarding the place of use of the LED driver, it is used for home lighting system.

Hi nanotronicsnss, I assume that you are using DER-526 as reference. To answer your questions more effectively, I will need more information regarding the design.

  • Does your design have the same specs as the reference DER?
  • Does the circuit function normally under 220VAC? 

 

To answer your questions:

1. I've provided reference materials below. It includes designing the line sense resistors, output compensation resistor, and the feedback RC.

2. As of now, I am not entirely sure of the cause of the resetting issue. I doubt that it is due to the line sense resistors. Maybe you can try changing back R1 and R2 to the default values and see how it affects the circuit. 

 

LYTSwitch-5 Design Guide: https://led-driver.power.com/design-support/product-documents/application-notes/an-65-lytswitch-5-design-guide/

LYTSwitch-5 Datasheet: https://led-driver.power.com/sites/default/files/product-docs/lytswitch-5_family_datasheet.pdf