How to set threshold of STEF01 Undervoltage Lockout (UVLO) feature
Hello. I am evaluating STEF01 for a PSU application.
I am trying to calculate the values for RH using the formula provided in the datasheet. But my calculation result for RH is not in line with chart given in figure 6 (page 8 of the datasheet). Referencing the chart, for a value of RL of 10K, and a required UVLO of 12V (=Von), I would expect RH around 60kOhm.
But my calculation is far apart from expected value:
From
RH = 1 / { [ (1/RL) + (1/333) / (Von-1) ] - [ 1/4500 ] }
I get 16,703 Ohms with Von=12 and RL=10k:
1 / { [(1/10000) + (1/333) / (12-1)] - [1/4500] } = 16,703
Very obviously my calculation is wrong, but why? Please advise, thank you.
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