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calculating voltage at base

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aamit4

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Hello:

what would the Voltage at point "E"? How would i calculate voltage at point "E"?

Thank you

Capture.PNG
 

dick_freebird

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Resistor divider, presuming there is no current flow in / out
of the off-page branch.
 

aamit4

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Thanks dick_freebird for your input.

Assume the off page branch is not connected to anything. here the modified image.

thanksCapture.PNG
 

Vbase

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Base voltage: 0.6V
Current: (3.3 - 0.6)/11K = 245uA
Voltage at E: 0.6V + 245uA * 1K = 0.845V
 
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    aamit4

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Audioguru

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You do not show the part number for the transistor for us to look at its datasheet. If it is a 2N3904 transistor then its saturated base voltage at a collector current of 10mA is somewhere in the range of 0.65V to 0.85V. There is a range because they cannot make transistors all the same, some have a higher base voltage than others and the temperature also affects the voltage.
 

Vbase

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You do not show the part number for the transistor for us to look at its datasheet. If it is a 2N3904 transistor then its saturated base voltage at a collector current of 10mA is somewhere in the range of 0.65V to 0.85V. There is a range because they cannot make transistors all the same, some have a higher base voltage than others and the temperature also affects the voltage.

Don't get me wrong, I love Canada but one thing for sure, in freezing Canada every transistor has a base voltage 300mV higher.
 

Audioguru

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Don't get me wrong, I love Canada but one thing for sure, in freezing Canada every transistor has a base voltage 300mV higher.
Some parts of Canada are very cold and transistors and people do not live there. I am in the southern party of Canada where there are some parts of USA north of me. The Great lakes near me keep the temperature moderate, maybe -10 degrees C is a very cold winter day. My 2N3904 transistors have maybe 10V and maybe 20mA so are nice and warm dissipating 200mW.
 

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