Common-Emitter Amplifier
Base
Collector
VCE
DC Supplies
Resistors
Transistor
AC Input Signal vin(t)
BJT Parameters (Silicon)
VBE(on) = 0.7 V • VCE(sat) = 0.2 V
VT = 26 mV (thermal voltage at 300 K)
re = VT / ICQ (small-signal emitter resistance)
rπ = β · re (base input impedance)
Av = −β · RC / (RB + rπ) (circuit gain, 180° inv.)
VT = 26 mV (thermal voltage at 300 K)
re = VT / ICQ (small-signal emitter resistance)
rπ = β · re (base input impedance)
Av = −β · RC / (RB + rπ) (circuit gain, 180° inv.)
iC vs vBE — Signal Transfer
IC vs VCE — Q-Point & Load Line
IB curves
DC load line
Q-point