Reverse Saturation Current of BJT

Asked Jan 16 '19 at 22:51

Active Jan 16 '19 at 23:24

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This may be a weird question but for a BJT, we have

\$I_S\$ is the reverse saturation current and \$I_C\$ is the collector current which flows through all three parts of the BJT.

Now my question is, \$I_S\$ should also flow through all three parts of the BJT, so can't we just add/subtract \$I_S\$ from \$I_C\$ via KCL? Is that where the -1 comes from?.

edited Jan 16 '19 at 23:24

TimWescott

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asked Jan 16 '19 at 22:51

AlfroJang80

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-1 is there to make the Ic zero when Vbe is zero. – user1245 Jan 16 '19 at 22:56
$I_S$ is a property of the transistor, not a physical current that actually flows through it. The $I_S$ in that equation is close to the reverse saturation current of the base-emitter junction, but the equation is off by a factor of $\beta$. – TimWescott Jan 16 '19 at 23:26
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I discuss it here and here. – jonk Jan 17 '19 at 03:06

Reverse Saturation Current of BJT

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