lecture 3 - mixedsignal | knowledge is power · pdf file · 2013-06-26lecture 3...

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Lecture 3Noise

George YuanHong Kong University of Science and Technology

Fall 2010

©

George Yuan, HKUST

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Outline

•

Introduction•

Device noise models

•

Circuit noise analysis•

Other noise sources–

Power noise

–

Substrate noise•

Noise reduction

•

Chopping

©

George Yuan, HKUST

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Main circuit problems

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George Yuan, HKUST

Linearity & Noise

THD

4

Vout

Characterization

©

George Yuan, HKUST

n

s

PP

SNR

nd

s

PPP

SINADSNDR

s

N

idi

P

PTHD

2

5

Noise in frequency domain

©

George Yuan, HKUST

fSV

6

Noise correlation

21 VVVeq

2212 VVVeq

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George Yuan, HKUST

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2121

22

21

221

2 2 VVVVVVVVVeq

Noise power

Equivalent noise

uncorrelated

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Power Spectral Density

2fHfSfS XY

©

George Yuan, HKUST

fH tX tY

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Noise Bandwidth

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George Yuan, HKUST

•

Noise power integration bandwidth?

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Outline

•

Introduction•

Device noise models

•



Power noise

–

Substrate noise•

Noise reduction

•

Chopping

©

George Yuan, HKUST

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Noise of a Resistor

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George Yuan, HKUST

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Integrated Noise of a Resistor (1)

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George Yuan, HKUST

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George Yuan, HKUST

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George Yuan, HKUST

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1/f Noise of a Resistor

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George Yuan, HKUST

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Shot Noise of a Diode

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George Yuan, HKUST

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1/f Noise of a Diode

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George Yuan, HKUST

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Noise of a MOS

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George Yuan, HKUST

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Equivalent Input Noise of a MOS

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George Yuan, HKUST

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Noise By Source Resistor R

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George Yuan, HKUST

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Source Resistance Rs

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George Yuan, HKUST

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Equivalent input noise: 1/f noise

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George Yuan, HKUST

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Noise vs. Current : corner fequency

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George Yuan, HKUST

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Outline

•

Introduction•

Device noise models

•



Power noise

–

Substrate noise•

Noise reduction

•

Chopping©

George Yuan, HKUST

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Noise of an amplifier with active load

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George Yuan, HKUST

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1/f Noise of an amplifier with active load

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George Yuan, HKUST

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Noise figure of an amplifier

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George Yuan, HKUST

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Resistive noise matching

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George Yuan, HKUST

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Noise of a Cascode Amplifier

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George Yuan, HKUST

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Input referred Noise of a Cascode

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George Yuan, HKUST

NSsdsmoutdsLL

sdsm iiRggvg

RRRgg

1

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Noise of a Folded Cascode

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George Yuan, HKUST

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Noise of a Cascode

with Linear M1

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George Yuan, HKUST

211

221

414

DS

eff

mon VkTV

gRkTdv

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Analysis

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George Yuan, HKUST

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Noise of Current Mirror

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George Yuan, HKUST

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Noise of Current Mirror with series R

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George Yuan, HKUST

2

1221

222

22

22

21

22

2

12

11m

mm

m

RRinout

diRg

diRg

dididiRRdi

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Noise Reduction of Current Mirror with series R

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George Yuan, HKUST

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Noise Reduction of CMOS Current Mirror with series R

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George Yuan, HKUST

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Noise of differential pair

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George Yuan, HKUST

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Noise of differential pair with active load

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George Yuan, HKUST

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Noise of differential pair with source resistor

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George Yuan, HKUST

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Noise of an OPAMP

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George Yuan, HKUST

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Capacitive Source Amplifier

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George Yuan, HKUST

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Capacitive Noise Matching (1)

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George Yuan, HKUST

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George Yuan, HKUST

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George Yuan, HKUST

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Outline

•

Introduction•

Device noise models

•



Power noise

–

Substrate noise•

Noise reduction

•

Chopping©

George Yuan, HKUST

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Ground

©

George Yuan, HKUST

1inch wire: 20nH/inch, a transient current: SR=10mA/ns

Δv = L = 20 nH

×

= 200 mVΔiΔt

10mAns

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Grounding for Mixed-signal IC

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George Yuan, HKUST

• DGND for mixed-signal IC should connect to analog ground plane• DGND couples to AGND• VD

separate to VA

by ferrite bead• Digital switching current absorbed by the decoupling cap path

• Separate digital output and data bus by a register

• Limiting current resistor R

56

Pad Frame, Down Bonding

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George Yuan, HKUST

1.

Tie the substrate to solid ground;

2.

Down bonding low impedance;

57

Outline

•

Introduction•

Device noise models

•



Power noise

–

Substrate noise•

Noise reduction

•

Chopping©

George Yuan, HKUST

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Circuit Noise Minimization

©

George Yuan, HKUST

•

Increase input gm•

Enlarge other transistors to reduce the flicker noise and thermal noise

•

Input transistor pair dominates the noise

•

Reduce the flicker noise of input transistors

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References

©

George Yuan, HKUST

1.

W. Sansen, Analog Design Essentials, Springer, 20062.

W. Kester, The Data Conversion Handbook, Analog Devices, 20053.

C. Enz, E. Vittoz, and F. Krummenacher, “A CMOS chopper amplifier”, IEEE J. Solid-State Circuits, Vol. SC-22, pp. 335-342, Jun. 1987

4.

R. Yazicioglu, P. Merken, R. Puers, and C. Van Hoof, “A 60uW 60nV/Hz0.5

readout front-end for portable biopotential

acquisition systems”, IEEE J. Solid-State Circuits, Vol. 42, pp. 1100-1110, May 2007

5.

R. Burt, and J. Zhang, “A micropower

chopper-stablized

operational amplifier using a SC notch filter with synchronous integration inside the continuous-time signal path”, IEEE J. Solid-State Circuits, Vol. 41, pp. 2729-2736, Dec. 2006

6.

J. Witte, J. Huijsing, and K. Makinwa, “A current-feedback instrumentation amplifier with 5uV offset for bidirectional high-side current-sensing”, IEEE J. Solid- State Circuits, Vol. 43, pp. 2769-2785, Dec. 2008

7.

B. Owens, S. Adluri, P. Birrer, R. Shreeve, S. Arunachalam, K. Mayaram, and T. Fiez, “Simulation and measurement of supply and substrate noise in mixed-signal ICs”, IEEE J. Solid-State Circuits, Vol. 40, pp. 382-391, Feb. 2005

lecture 3 - mixedsignal | knowledge is power · pdf file · 2013-06-26lecture 3...

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