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Incorrect Output Voltage from ADP2119ACPZ-1.2-R7

Dear Team,

Kindly refer to the schematic snapshot below for ADP2119ACPZ-1.2-R7.

We are getting 0.6V at the output of this regulator at inductor L1 even though this is a fixed output voltage regulator. The branding of LFK printed at the regulator confirms that it is ADP2119ACPZ-1.2-R7.

However when I mount 10K resistor at both R10 & R12 of ADP2119ACPZ-1.2-R7, the output comes as desired as 1.2V as per below formula for adjustable output version.

Since this is a fixed output regulator rather adjustable version, why do we need to mount both RTOP & RBOTTOM  at this regulator. Ideal case should be as per above circuit diagram.

I am also using ADP2119ACPZ-1.8-R7 in the same board, and it gives correct output as desired with RTOP = 0E & RBOTTOM = DNM as shown in schematic below:

What is the reason of this misbehavior of ADP2119ACPZ-1.2-R7?

Kindly note that both these ICs were procured as free sample from ADI Website for our prototype development.

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