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BiPolar transistor calculation

Copper_pipe · 2014-10-17 21:52:44

Here is the problem I am having trouble with, Im not sure what to do with the tolerances on the resistors. http://i.gyazo.com/2261407b9a5ece37aaa1c15ca6ddeeb9.png my attempt is below :

17-10-2014 10:52PM

#1

Copper_pipe

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Posts: 11231

Here is the problem I am having trouble with, Im not sure what to do with the tolerances on the resistors.

http://i.gyazo.com/2261407b9a5ece37aaa1c15ca6ddeeb9.png

my attempt is below :

0

Comments

#2 17-10-2014 11:39PM

DublinDilbert

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Join Date: July 2006

Posts: 5158

Copper_pipe wrote: »

Here is the problem I am having trouble with, Im not sure what to do with the tolerances on the resistors.

http://i.gyazo.com/2261407b9a5ece37aaa1c15ca6ddeeb9.png

my attempt is below :

For max current take 5% off the 220k base resistor and calc the base current. This will be the max base current and times 75 gives the collector current.

The max collector emitter voltage will happen at the smallest base current, so add 5% on to the 220k. I think for this calc you must also factor in the collector resistor, so I'd sub 5% off the 2k

0