I am using LT8315 as a buck converter for converting 363V to 15V @0.2A.IC is worked fine. Recently we had the failure in LT8315 with controller which shows burnt mark.The output capacitor also burnt and impedance is measured as short.The impedance across the IC pin 1(drain) and pin 20(ground) is measured as open.
Can you suggest the reason for failure in LT8315.
Make sure the output inductor has sufficient voltage rating, at least 363V.
The maximum switch current of the LT8315 over the temperature should be limited to 300mA, as shown in the electrical characteristic table on page 3. Since the buck converter operates in boundary conduction mode, the maximum output current would be less than half of the switch current. Therefore, the LT8315 buck converter should only be designed for an output current less than 150mA.
If more output current is needed, the LT8316 can be considered. The buck converter example can be found in its datasheet.
Inductor Voltage rating:400V
Switch current limit:270mA
IC failed again with the same burnt mark.
So far, we faced failure in 2 units in a month time.
What would be the root cause for the failure.
Refer the Schematics attached in previous discussion and suggest a solution.
Switch current limit :270mA
Again the IC failed with same burnt mark after replacing inductor with HV inductor.
So far, we had failure in 2units in a month.
What would be the reason for the failure?
Refer the attached Schematics in earlier discussion and suggest a solution as soon as possible.
Please reach out to a local ADI support team or an FAE.