What are the advantages of using constant current bias instead of emitter bias in differential amplifier?
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Differential amplifier is an electronic amplifier which amplifies the difference in between the input voltages but suppresses the common voltage in between the 2 inputs.
It is important for the quiescent current to be constant so that there is constant collector voltage at the common mode.
The emitter current IE depends upon the value of dc and the current IE should be constant irrespective value
dc.
For a constant IE, the RE should be very high, which increases the CMRR value. If the RE value increases, then the IE (quiescent operating current) decreases.
Therefore, to get a very high value of resistance RE and constant IE, a constant current bias is used.
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