POWER OPTIMIZATION OF CMOS PROGRAMMABLE GAIN AMPLIFIERS WITH HIGH DYNAMIC RANGE AND COMMON-MODE FEED...
This presentation is the property of its rightful owner.
Sponsored Links
1 / 50

A. J. Ginés*, R. Doldán, A. Rueda and E. Peralías PowerPoint PPT Presentation


  • 60 Views
  • Uploaded on
  • Presentation posted in: General

POWER OPTIMIZATION OF CMOS PROGRAMMABLE GAIN AMPLIFIERS WITH HIGH DYNAMIC RANGE AND COMMON-MODE FEED-FORWARD CIRCUIT. A. J. Ginés*, R. Doldán, A. Rueda and E. Peralías Instituto de Microelectrónica de Sevilla (CNM-CSIC) University of Seville (Spain). IEEE ICECS 2010. Contents. Motivations

Download Presentation

A. J. Ginés*, R. Doldán, A. Rueda and E. Peralías

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


POWER OPTIMIZATION OF CMOS PROGRAMMABLE GAIN AMPLIFIERS WITH HIGH DYNAMIC RANGE AND COMMON-MODE FEED-FORWARD CIRCUIT

A. J. Ginés*, R. Doldán, A. Rueda and E. Peralías

Instituto de Microelectrónica de Sevilla (CNM-CSIC)University of Seville (Spain)

IEEE ICECS 2010


Contents

  • Motivations

  • State-of-the-Art in Low Voltage PGAs

    • Close-loop vs. Open-loop Architectures

  • Proposed PGA Architecture

    • Design Methodology

    • Common-Mode Feed-forward Circuit (CMFFC)

  • Verification:

    • Post-layout Simulation Results (3-stage PGA)

    • Experimental Results (stage core)

  • Conclusions


Motivations

  • Low-IF ZigBee Receiver

  • ZigBee should operate with power levels at the antenna from -85dBm to -20dBm (DR > 64dB).

  • Adjustable gain through the chain is need to optimize the sensitivity and signal-to-noise ratio (SNR).

  • Power consumption is one of the most critical design constraints in ZigBee standard.

1


Motivations

  • Low-IF ZigBee Receiver

This Work

  • ZigBee should operate with power levels at the antenna from -85dBm to -20dBm (DR > 64dB).

  • Adjustable gain through the chain is need to optimize the sensitivity and signal-to-noise ratio (SNR).

  • Power consumption is one of the most critical design constraints in ZigBee standard.

1


Contents

  • Motivations

  • State-of-the-Art in Low Voltage PGAs

    • Close-loop vs. Open-loop Architectures

  • Proposed PGA Architecture

    • Design Methodology

    • Common-Mode Feed-forward Circuit (CMFFC)

  • Verification:

    • Post-layout Simulation Results (3-stage PGA)

    • Experimental Results (stage core)

  • Conclusions


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

G = Rf / Rin

2


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

  • Take advantage of resistive feedback to achieve:

  • High Linearity

  • Low Noise

G = Rf / Rin

2


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

  • Take advantage of resistive feedback to achieve:

  • High Linearity

  • Low Noise

  • Drawbacks of the classical approach:

  • Gain programmability introduces stability issues.

  • Low voltage limitations due to equal common modes (cmi = cmo).

  • Buffers are required to deal with low input impedance.

G = Rf / Rin

2


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

  • Take advantage of resistive feedback to achieve:

  • High Linearity

  • Low Noise

  • Drawbacks of the classical approach:

  • Gain programmability introduces stability issues.

  • Low voltage limitations due to equal common modes (cmi = cmo).

  • Buffers are required to deal with low input impedance.

G = Rf / Rin

Current Division Network (CDN)

Reference: [3]

2


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

  • Take advantage of resistive feedback to achieve:

  • High Linearity

  • Low Noise

  • Drawbacks of the classical approach:

  • Gain programmability introduces stability issues.

  • Low voltage limitations due to equal common modes (cmi = cmo).

  • Buffers are required to deal with low input impedance.

G = Rf / Rin

Decoupling common mode (cmi ≠ cmo)

Reference: [4]

2


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

  • Take advantage of resistive feedback to achieve:

  • High Linearity

  • Low Noise

  • Drawbacks of the classical approach:

  • Gain programmability introduces stability issues.

  • Low voltage limitations due to equal common modes (cmi = cmo).

  • Buffers are required to deal with low input impedance.

G = Rf / Rin

Transimpedance amplifier

Reference: [6]

2


State-of-the-Art in Low Voltage PGAs

  • Close-loop Architectures

  • Take advantage of resistive feedback to achieve:

  • High Linearity

  • Low Noise

G = Rf / Rin

  • Main drawback for ZigBee:

  • High power consumption is required for driving resistive load.

  • It does not take advantage of the standard linearity relaxation.

Solution: Open-loop topologies !!!

2


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures

G = gmRo

3


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures

  • Advantages:

  • High-speed and high-stability

  • Low-Power

G = gmRo

Gilbert’s Cell

References: [8-10]

3


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures

  • Advantages:

  • High-speed and high-stability

  • Low-Power

  • Drawbacks:

  • Gain is not accurately defined.

  • Low-voltage operation.

  • Non-linearity

G = gmRo

Gilbert’s Cell

References: [8-10]

3


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures

  • Advantages:

  • High-speed and high-stability

  • Low-Power

  • Drawbacks:

  • Gain is not accurately defined.

  • Low-voltage operation.

  • Non-linearity

G = gmRo

Gilbert’s Cell

References: [8-10]

3


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures

  • Advantages:

  • High-speed and high-stability

  • Low-Power

  • Drawbacks:

  • Gain is not accurately defined.

  • Low-voltage operation.

  • Non-linearity

G = gmRo

Gilbert’s Cell

References: [8-10]

3


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures with Feed-back

Resistive degeneration enhances linearity

4


State-of-the-Art in Low Voltage PGAs

  • Open-loop Architectures with Feed-back

Resistive degeneration enhances linearity

Further Improvement

This Work

References: [18-22]

Gain Boosting

Servo-loop [20,21]

Super-Source Follower (SSF) [18,19]

4


Contents

  • Motivations

  • State-of-the-Art in Low Voltage PGAs

    • Close-loop vs. Open-loop Architectures

  • Proposed PGA Architecture

    • Design Methodology

    • Common-Mode Feed-forward Circuit (CMFFC)

  • Verification:

    • Post-layout Simulation Results (3-stage PGA)

    • Experimental Results (stage core)

  • Conclusions


Proposed Low Power PGA Architecture

  • A 1.2V 72dB 3-stage PGA in 90nm CMOS process

5


Proposed Low Power PGA Architecture

  • A 1.2V 72dB 3-stage PGA in 90nm CMOS process

5


Proposed Low Power PGA Architecture

  • A 1.2V 72dB 3-stage PGA in 90nm CMOS process

How much currents in 90nm CMOS?

Stress due to trench isolation barriers!!!

5


Proposed Low Power PGA Architecture

  • A 1.2V 72dB 3-stage PGA in 90nm CMOS process

How much currents in 90nm CMOS?

Stress due to trench isolation barriers!!!

All the transistors have

the same width, length

and number of fingers.

The only difference is the multiplicity.

5


Proposed Low Power PGA Architecture

  • A 1.2V 72dB 3-stage PGA in 90nm CMOS process

Gain

Poles

Zero

5


Proposed Low Power PGA Architecture

  • Design Methodology

Specifications

G BW Power

THD OS Noise

VDD Ib C0ω2

6


Proposed Low Power PGA Architecture

  • Design Methodology

Specifications

G BW Power

THD OS Noise

VDD Ib C0ω2

Initial

guess

cmo, cmi

6


Proposed Low Power PGA Architecture

  • Design Methodology

Specifications

G BW Power

THD OS Noise

VDD Ib C0ω2

Initial

guess

Formulae

BW, C0 R0

cmo, cmi

cmo, R0 F5

6


Proposed Low Power PGA Architecture

  • Design Methodology

Specifications

G BW Power

THD OS Noise

VDD Ib C0ω2

Initial

guess

Formulae

Formulae

Pick Values

G, ω2 F3

BW, C0 R0

Fs=R0/RS

FN

cmo, cmi

W1, W5, W4, WBP, WBN

cmo, R0 F5

OP-AC

Simulation

NO

BW, Noise ?

6


Proposed Low Power PGA Architecture

  • Design Methodology

Specifications

G BW Power

THD OS Noise

VDD Ib C0ω2

Initial

guess

Formulae

Formulae

Pick Values

G, ω2 F3

BW, C0 R0

Fs=R0/RS

FN

cmo, cmi

W1, W5, W4, WBP, WBN

cmo, R0 F5

OP-AC

Simulation

NO

NO

BW, Noise ?

YES

PSS

Simulation

END

THD, Power ?

YES

6


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

7


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

1.- AC-coupling

2.- CMFF Circuit

7


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

1.- AC-coupling

2.- CMFF Circuit

AC-coupling

7


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

1.- AC-coupling

2.- CMFF Circuit

AC-coupling

  • Traditional assumptions for PGAs, such as the convenience of DC-coupling [1], must be revised in a low-voltage high-dynamic range scenario

S = 2 (Vinpmax- Voutpmin)

≈ 0.28Vpp

S = 2 (Vinp,outpmax- Vinp,outpmin)

> 0.90Vpp

VDD/2

0.4

0.4

DC-coupled

AC-coupled

0.2

0.2

-0.2

Voltage Range (V)

-0.2

Voltage Range (V)

7


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

1.- AC-coupling

2.- CMFF Circuit

AC-coupling

  • Traditional assumptions for PGAs, such as the convenience of DC-coupling [1], must be revised in a low-voltage high-dynamic range scenario

S = 2 (Vinpmax- Voutpmin)

≈ 0.28Vpp

S = 2 (Vinp,outpmax- Vinp,outpmin)

> 0.90Vpp

VDD/2

  • Advantages:

  • Different cmi and cmo

  • Greater dynamic range

  • High linearity without resistive feedback

  • Low-power consumption

0.4

0.4

DC-coupled

AC-coupled

0.2

0.2

-0.2

Voltage Range (V)

-0.2

Voltage Range (V)

7


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

1.- AC-coupling

2.- CMFF Circuit

8


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

Common-Mode Feed-forward Circuit (CMFF)

8


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

Common-Mode Feed-forward Circuit (CMFF)

( common for all stage)

8


Proposed Low Power PGA Architecture

  • Key Aspects in the Design

Common-Mode Feed-forward Circuit (CMFF)

  • Advantages:

  • Common-mode feedback circuit can be suppressed since relatively low impedance is found at the output (Ro is usually in the order of k).

  • Low-cost low-power solution.

  • Accurately definition of the output common-mode (cmo).

  • Functionality guaranteed with Corners and Monte-Carlo simulations.

( common for all stage)

8


Contents

  • Motivations

  • State-of-the-Art in Low Voltage PGAs

    • Close-loop vs. Open-loop Architectures

  • Proposed PGA Architecture

    • Design Methodology

    • Common-Mode Feed-forward Circuit (CMFFC)

  • Verification:

    • Post-layout Simulation Results (3-stage PGA)

    • Experimental Results (stage core)

  • Conclusions


Verification: 3-stage PGA

  • Target Specifications

    • Gain = 0 to 72dB in 6-dB steps

    • Bandwidth > 15MHz

    • ω 2 >> BW

    • Power < 2.5mW

    • Input referred noise (Gmax) < 15nVrms /Hz

    • THD (Gmax) < -36dB

    • Vdd = 1.2V  5%

9


Verification: 3-stage PGA

  • Post-layout Simulation Results (90nm CMOS)

Active Section

65µm

3-stg PGA

Decoupling Network

165µm

STG Layout

Stage-core

110µm

9


Verification: 3-stage PGA

  • Corners and Monte-Carlo Specifications (Post-layout)

10


Verification: 3-stage PGA

  • Corners and Monte-Carlo Specifications (Post-layout)

10


Verification: 3-stage PGA

  • Corners and Monte-Carlo Specifications (Post-layout)

10


Verification (not included in the paper)

  • Experimental Results (single stage)

Gain ↑

PCB Test Setup +

HP3589A Analyzer

Simulated: - -

Measured: ―

Single-to-Differential Input Buffers

& Diff.-to-Single Output Buffers

This work has been partially supported by the Spanish projects TEC2007-68072 and P09-TIC-5386, and by the Catrene European project SR2 2A105 (all co-founded by FEDER).

11


Verification (not included in the paper)

  • Experimental Results (single stage)

PCB Test Setup +

HP3589A Analyzer

Single-to-Differential Input Buffers

& Diff.-to-Single Output Buffers

This work has been partially supported by the Spanish projects TEC2007-68072 and P09-TIC-5386, and by the Catrene European project SR2 2A105 (all co-founded by FEDER).

11


Contents

  • Motivations

  • State-of-the-Art in Low Voltage PGAs

    • Close-loop vs. Open-loop Architectures

  • Proposed PGA Architecture

    • Design Methodology

    • Common-Mode Feed-forward Circuit (CMFFC)

  • Verification:

    • Post-layout Simulation Results (3-stage PGA)

    • Experimental Results (stage core)

  • Conclusions


Conclusions

  • In this paper, we have shown that open-loop topologies with gain boosting present an optimum trade-off between power consumption and linearity for ZigBee applications.

  • We have proposed a design methodology for low-voltage PGAs with resistive degeneration.

  • The developed design flow is shown with a 1.2V 72dB 1.95mW PGA implementation in a TSMC 90nm CMOS process.

  • Power optimization is improved thanks to the use of a front-end capacitive decoupling network and a common-mode feed-forward circuit shared between all stages.

  • The front-end capacitive decoupling network also improves the PGA dynamic range. Actually, a THD < -42dB is achieved for a 1.2Vpp output excursion, G = {4,8,16}.

12


POWER OPTIMIZATION OF CMOS PROGRAMMABLE GAIN AMPLIFIERS WITH HIGH DYNAMIC RANGE AND COMMON-MODE FEED-FORWARD CIRCUIT

Thank you very much for your attendance

Questions?

A. J. Ginés, Email: [email protected]

Instituto de Microelectrónica de Sevilla (CNM-CSIC)University of Seville (Spain)


  • Login