sjamil02
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Hi All,
In PE Holberg book, pp186. "The way that ICMR is found is to set VID to zero and vary common mode input until one of the transistor in the differential amplifier is no longer saturated".
I have tried this in simulation. I am using nmos input differential amplifier with current mirror load. As you see in the waveform,
VDS4=VGS4-VT @ 1.2V common mode input (Nmos input transistor M4)
VDS3=VGS3-Vt @ 1.5V common mode input (Nmos tail transistor M3)
What is ICMR in this case? It seem there is no input common mode voltage that can satisfy both transistor M4 and M3 to be in saturation.
cheers
sj
In PE Holberg book, pp186. "The way that ICMR is found is to set VID to zero and vary common mode input until one of the transistor in the differential amplifier is no longer saturated".
I have tried this in simulation. I am using nmos input differential amplifier with current mirror load. As you see in the waveform,
VDS4=VGS4-VT @ 1.2V common mode input (Nmos input transistor M4)
VDS3=VGS3-Vt @ 1.5V common mode input (Nmos tail transistor M3)
What is ICMR in this case? It seem there is no input common mode voltage that can satisfy both transistor M4 and M3 to be in saturation.
cheers
sj
