Typical Performance Characteristics
Distortion vs Differential
Input Voltage
(Continued)
Voltage vs Amplifier
Bias Current
Output Noise vs Frequency
DS007981-52
DS007981-50
DS007981-51
Unity Gain Follower
DS007981-5
Leakage Current Test Circuit
Differential Input Current Test Circuit
DS007981-6
DS007981-7
Circuit Description
The differential transistor pair Q
4
and Q
5
form a transcon-
ductance stage in that the ratio of their collector currents is
defined by the differential input voltage according to the
transfer function:
(1)
where V
IN
is the differential input voltage, kT/q is approxi-
mately 26 mV at 25˚C and I
5
and I
4
are the collector currents
of transistors Q
5
and Q
4
respectively. With the exception of
5
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