CMOS RFIC Noise Canceling Method

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CMOS RFICNoise Canceling Method

• 2009314086 An Yong-jun

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Contents
Noise Cancelling in Wideband CMOS LNAs F.
Bruccoleri, E.A.M. Klumperink, B. Nauta. In 2002,
ISSCC
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Paper Study Flow
Today

• Noise Cancelling in Wideband CMOS LNAs
• F. Bruccoleri, E.A.M. Klumperink, B. Nauta. In
  2002, ISSCC

Same Circuit
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Noise Cancelling in Wideband CMOS LNAs
For input matching Zin Rs ? NFgt3dB NF always
lager than 3dB
Shunt Feedback
Input noise current (ACL-1)times smaller than the
others
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Noise Cancelling in Wideband CMOS LNAs
Noise Canceling from MOSFET (Not source)
? Determine A
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
Same
Opposite
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
Overall Gain
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
Source Follower
Vout VYoutVXout VYout VY VXout VX gm2/gm3
Noise cancelled which is generated by this FET
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
Less than 1
EF (noise)Excess Factor
Higher gm2Rs ? Lower F
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
Noise cancelled point!
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling

• Robustness

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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling

• Distortion canceling

Distortion comes from this FET
Distortion canceled like Thermal noise
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling

• High Freq. Limit.

Approximately CYCL0

1. CY and the load CL dont affect the cancellation
2. CL doesnt affect the F of the LNA standalone

Source Impedance looks like
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
_at_ High Freq, Noise cancelling is degraded
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
But f0 is higher, - high fT - Minimizing
CIN - reduce Miller effect degrades frequency
factor
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling
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Wide-Band CMOS Low-Noise Amplifier Exploiting
Thermal Noise Canceling

• Conclusion
• simultaneous cancellation of noise and
  distortion terms
• due to the matching device
• simultaneous noise and power matching for
  frequencies
• where the effect of parasitic capacitors can be
  neglected
• orthogonality of design parameters for input
  impedance
• and gain, allowing for an easier implementation
  of variable
• gain while maintaining input impedance
  matching
• robustness to variations in device parameters
  and the external
• source resistance
• applicability in other IC technologies and
  amplifier
• topologies.