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Q: TPS61181 recommended replacement for schottky diode by 9312
On p 16 of the datasheet for the TPS61181RTET a schottky diode is used and recommended and this part # is SS2P5-E3/84A at 50V
He has found another part # SS2P4-E3/84A which is 40V
Can he replace the SS2P5-E3/84A with the SS2P4-E3/84A?
A: Re: TPS61181 recommended replacement for schottky diode by 1090425
It depends on how many LEDs in series they are driving and how much margin they want on the diode's voltage rating. The maximum reverse voltage that the diode could see is the output voltage (forward voltage of all the LEDs in series). Since the IC has an OVP circuit that clamps the output voltage at 39V typical, 40V maximum, a 40V diode gives zero margin on its voltage rating if one of the LEDs opens and the OVP circuit activates. In the datasheet on pages 12 and 13 are other explanations of why the OVP might be triggered. Operating with 0 margin on the diode is not recommended.