Hello!
I’m currently designing a PCB for a laser driver and in the laser driver’s datasheet states that I need to use a 0.33 ohm resistor.
So like many other people, I Googled “0.33 Ohm resistor DigiKey” the following two components popped up
# MP915-0.33-1%
# SMW7R33JT
Both items in the description field state they’re 0.33-ohm resistors
But in the product attributes both have a resistance value of 330 ohms
Since I don’t want to mess up my PCB design on a silly mistake as far as using the wrong resistor value, the big question I wanted to ask is if my laser driver needs a 0.33-ohm resistor, can I use either of the resistors I mentioned in this post in my PCB design?
My gut feeling says yes, but I wanted to double-check with y’all first before pulling the trigger
Welcome to the technical forum. You can use these resistors. In the attributes section they are listed as 330 mohm (note: the leading “m” refers to milli-Ohms rather than Ohms) which would be 0.33 ohms. We do have many options for .33 ohms that are different typess. You can check out this link: https://www.digikey.com/en/products/filter/through-hole-resistors/53?s=N4IgjCBcoEwAwA4CsVQGMoDMCGAbAzgKYA0IA9lANogDMNcABALYDyAFk-iALqkAOAFyggAqgDsAlgJaYAsoWz4ArgCdCIAL6kAtDFQgMkASqUlyVECm5aQ2gJz7Dx06QqRqEaxo1A’
I am not sure why we list the milliohm value in the attributes and the ohm rating in the description. Hopefully this will help.
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…I totally didn’t see the leading “M” to be honest because I was skimming
But I do appreciate you pointing that out!
Be very careful reading and writing unit of measurement prefixes, you definitely did not see an “M” you saw an “m” which is 1,000,000,000 times lower in resistance value.
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