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Hi all,does anyone know the amount of voltage drop across a 450nm m-140 ld

m3vuv

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I am trying to work out how many .6v drops across diodes to make a dummy load,cant see how many diodes i need,its a m -140 2 watt diode im trying to simulate to set the driver current,cheers m3-vuv.
 



Immo1282

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You have to also bear in mind the voltage drop across the current shunt resistor you end up using. - so V=I*R for the current measurement and the measured shunt value (don't use the quoted value, measure the shunt yourself).

I think the datasheet operating range for the M140 is 3.7V-5.5V so anecdotally use 5-7 diodes :)
 

diachi

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Check the datasheet for the diodes you're using in your dummy load too, voltage drop across a regular rectifier diode shifts with changes in current/temperature.
 




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