Experiment 7

Common terminal

The "shared reference" for input and output in BJT config is the _

CB, CE, CC

Three BJT circuit configurations are _

Common Base (CB)

BJT config with input at Emitter, output at Collector is _

Common Emitter (CE)

BJT config with input at Base, output at Collector is _

Common Collector (CC)

BJT config with input at Base, output at Emitter is _

Common Emitter (CE)

BJT config used for general-purpose power amplification is _

Common Base (CB)

BJT config used for RF/high-frequency impedance matching is _

Common Collector (CC)

BJT config used as an emitter follower/buffer is _

180

Phase shift introduced ONLY by Common Emitter (CE) is _

0

Phase shift of Common Base (CB) configuration is _

0

Phase shift of Common Collector (CC) configuration is _

Emitter follower

Common Collector (CC) is also called _

approx 1 (unity)

Voltage gain of Common Collector (CC) is _

Very high

Input impedance of Common Collector (CC) is _

Very low

Output impedance of Common Collector (CC) is _

Very low

Input impedance of Common Base (CB) is _

Very high

Output impedance of Common Base (CB) is _

Moderate

Input impedance of Common Emitter (CE) is _

Moderate

Output impedance of Common Emitter (CE) is _

CB

Which BJT config has highest voltage gain? _

Highest

Current gain of Common Emitter (CE) is _

a < 1

Current gain of Common Base (CB) is _

b + 1

Current gain of Common Collector (CC) is _

IE

CB configuration input current is _

IC

CB configuration output current is _

IB

CE configuration input current is _

IC

CE configuration output current is _

IB

CC configuration input current is _

IE

CC configuration output current is _

a = b/(b+1)

Relationship: α in terms of β is _

b = a/(1−a)

Relationship: β in terms of α is _

Slightly less than 1

CB current gain (α) value is always _

50–300

Typical range of β (CE current gain) is _

Recombination in Base region

Why α < 1: some carriers are lost to _