Hi everyone,
I am trying to make constant 30mA current source. I wanted to use lm317 but it have 1.7V of dropout voltage. can you suggest another one with lower dropout voltage. Load is approximately 130ohm.
Thank you for advice
* I didn't say that maximum voltage for input pin is 5V. If I use Lm317 for input voltage I need ~8V. I found these voltage regulator http://www.farnell.com/datasheets/62273.pdf
If I set current of 30mA with R1 then output voltage is ( 0.8*(1+R2/R1)=4.7V -- R1=130ohm - load ). Now I can use 5V for input pin or not?
I am trying to make constant 30mA current source. I wanted to use lm317 but it have 1.7V of dropout voltage. can you suggest another one with lower dropout voltage. Load is approximately 130ohm.
Thank you for advice
* I didn't say that maximum voltage for input pin is 5V. If I use Lm317 for input voltage I need ~8V. I found these voltage regulator http://www.farnell.com/datasheets/62273.pdf
If I set current of 30mA with R1 then output voltage is ( 0.8*(1+R2/R1)=4.7V -- R1=130ohm - load ). Now I can use 5V for input pin or not?
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