hi friends please show me how can i calculate resistor value connected to base of 2n2222? thanks
E eplanet Mar 5, 2007 88 Joined Mar 5, 2007 Messages 88 Feb 15, 2012 #2 hi friends please show me how can i calculate resistor value connected to base of 2n2222? thanks View attachment 41659
hi friends please show me how can i calculate resistor value connected to base of 2n2222? thanks View attachment 41659
Hero999 Oct 28, 2007 2,433 Joined Oct 28, 2007 Messages 2,433 Feb 15, 2012 #3 Assuming Vcc is the same as the voltage powering the MCU, as a general turle of thumb, make the base resistor 10 times the value of the relay's coil resistance.
Assuming Vcc is the same as the voltage powering the MCU, as a general turle of thumb, make the base resistor 10 times the value of the relay's coil resistance.
E eplanet Mar 5, 2007 88 Joined Mar 5, 2007 Messages 88 Feb 15, 2012 #4 thanks hero999 is there any formula for this issue? my coil is 57ohm Last edited by a moderator: Feb 15, 2012
