Transcript cicc08_60GHz_radio.v.. - University of Toronto

A Zero-IF 60GHz Transceiver in 65nm
CMOS with > 3.5Gb/s Links
Alexander Tomkins, Ricardo A. Aroca, Takuji Yamamoto*, Sean T.
Nicolson, Yoshiyasu Doi* and Sorin P. Voinigescu, University of
Toronto, Toronto, Canada, *Fujitsu Laboratories, Kawasaki, Japan
University of Toronto 2008
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System Description
Bias
VDD
RFin
TX+
Mixer
IF+
IF-
LNA
BPSK
Modulator
LO
Tree
18mA
Div
18mA
18mA
VDD
Data
Buffers
12mA
Bias
Datain
LOin
Fundamental frequency, zero-IF
architecture
Divider
÷2
TX-
Simple architecture appropriate for rapid
file-transfer -> “Kiosk” applications
LO
Buffer
Direct BPSK modulation/demodulation
Baseband NRZ data recovered with no
ADC
Single-chip with TX and RX integration
Design completed in 3-4 weeks (4 designers), with an immature design-kit
Performed hand design with only DC sims and no layout parasitic extraction tool.
Designed for 60GHz + 10%
Alexander Tomkins – University of Toronto
2008
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Circuit Design Philosophy in CMOS
*A 65nm CMOS wafer costs more than a 300GHz SiGe BiCMOS wafer*
CMOS does not make economic sense unless you integrate the DSP
You must ensure that all topologies can scale to 45nm, 32nm ...
VDD
Tradition cascode stages:
VDD ≥ 1.0V
Require VDD≥1.0
VDS will vary as a result of VT variation
∆ VT
Different topologies are required in order to:
∆VDS due to ∆ VT
Work with VDD < 0.9V
VT insensitive
Alexander Tomkins – University of Toronto
2008
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Circuit Design Philosophy in CMOS
Folded-cascode topologies with constant current biasing
Only one high-speed transistor is placed between VDD and ground,
maximizing the transistor VDS.
All mm-wave blocks can be implemented with these topologies:
VDD
VDD
VDD
AC-folded
Cascode
Vout+
VoutLO+
LO-
LO-
VG
Ibias
XFMR-folded
Cascode
XFMR
VIN+
VDD
Ibias
But there is a price: 2x the current
Alexander Tomkins – University of Toronto
2008
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Low-Noise (Power) Amplifier
M1, M2: 30x0.8umx60nm
VDD
M3: 38x0.8umx60nm
M4, M5: 50x0.8umx60nm
M6: 62x0.8umx60nm
120pH
VDD
VG
120pH
+
VDD
130fF
VG
120pH
250pH
VOUT
M6
130fF
92fF
M5
M3
M1
VIN
VG
M4 100pH
130fF
92fF
250pH
VDD 90pH
100pH
-
M2 100pH
1pF
VDD
VDD
100pH
100pH
120pH
Input is noise and impedance matched to 50Ω, with large output transistors for IIP3 and OP1dB
80mA (60mA) from 1.2V (1.0V)
High gain to reduce receiver NF variation with temperature/process
Alexander Tomkins – University of Toronto
2008
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Direct BPSK Modulator and Mixer
VDD=1.2V
VDD=1.2V
50Ω
90pH
90pH
Vout+
Vout+
-
DATA
Vout40um
800Ω
VLO-
41.6um
LO+
VDD=1.2V
0.77mA
59.2um
R=300Ω
12mA
2-coil
XFMR
VDD=1.2V
VDD=1.2V
40um
DATA
40um
2-coil
XFMR
59.2um
LO+c
40um
-
VDD=1.2V
0.77mA
Vout-
LO-
DATA+
VDD=1.2V
50Ω
R
59.2um
59.2um
4kΩ
R
VDD=1.2V
VLO+
R
800Ω
From LNA
2.4um
18mA
81.6um
20mA
83.2um
2.4um
81.6um
20mA
Data signal directly drives quad transistors of modulator [in SiGe: C. Lee
et al, CSICS 2004]
Equivalent to a digitally modulated PA; operates in saturation
Both circuits drive off-chip directly in 50Ω (mixer has no IF amplifier)
Alexander Tomkins – University of Toronto
2008
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New Frequency Divider Topology
220um
Merged latching quads
minimize feed-back path
CML buffer stage
85um
VDD=1.2V
VDD=1.2V
50Ω
330pH
Diagonally symmetric
transformers
50Ω
50Ω
330pH
330pH
50Ω
330pH
Compact
divider core
Vout+
Vout-
20um
Single differential pair drives
both latches:
Reduces footprint,
increases speed
20um
20um
51.2um 12mA
51.2um 12mA
2-coil
XFMR
CLK+
20um
VDD=1.2V
2-coil
XFMR
0.77mA
32um
32um
800Ω
CLK-
2.4um
18mA
saves power and area
Alexander Tomkins – University of Toronto
2008
VDD=1.2V
60.8um
1pF
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Transceiver Implementation – Die Photo
Divider
Div Out
LNA
Mixer
LO Tree
0.81mm
1.28mm
LO in
IF Out+
TX Out+
RX in
IF Out-
Alexander Tomkins – University of Toronto
2008
Data in
TX Out-
BPSK
Modulator
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Transceiver Implementation - Technology
Fujitsu 65nm CMOS
7-metal back-end, MiM capacitors
Alexander Tomkins – University of Toronto
2008
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Low-Noise (Power) Amplifier
Measurements
20
20
S11
15
S21
5
25
10
0
5
5
0
0
-5
-5
-10
-10
-15
-15
-20
40
30
50
60
-20
70
58GHz, 25C
58GHz, 85C
20
-5
15
-10
10
-15
o
@25 C = -14dBm
-20
-30
-20
o
@85 C = -12dBm
-10
0
5
0
10
Pin (dBm)
Frequency (GHz)
Peak gain of ~19dB, S11 better than -10dB up to 65GHz
25oC, 1.2V: IP1dB = -14dBm, OP1dB = +2.5dBm, PSAT = +7.5dBm
Alexander Tomkins – University of Toronto
2008
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Gain (dB)
10
Pout (dBm)
S-Parameters (dB)
15
10
Frequency Divider Measurement (from TXRX)
Alexander Tomkins – University of Toronto
2008
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Measured Receiver Gain and NF over
Process Corners
Alexander Tomkins – University of Toronto
2008
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Measured Receiver Gain and NF Over
Temperature and Power Supply
Alexander Tomkins – University of Toronto
2008
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Measured Transmitter Output Power vs.
Frequency over Temperature and VDD
61GHz Carrier, 4.0Gbps 27-1
PRBS Signal
Alexander Tomkins – University of Toronto
2008
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Transmit-Receive Link Experiment
Signal Source
0 - 12 GHz
Agilent 20GHz
Digital Scope
Trigger
Power
Splitter
Clock
Channel 4
Channel 3
Out-
IF Amp
35dB
4GHz BW
5
~2m
Transceiver
(Receive Mode)
60 GHz
LO
Out+
Data
IF
DC
Signals
Centellax
PRBS
Generator
0 – 12.5 Gbit/sec
Transceiver
(Transmit Mode)
Horn
Antenna
25dBi
Horn
Antenna
25dBi
Agilent
Signal Source
0 - 67 GHz
10 MHz Sync Signal
Alexander Tomkins – University of Toronto
2008
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DC
Signals
60 GHz LO
Millitec 4x Multiplier
50 – 75 GHz
15 GHz
HP
Signal Source
0 - 50 GHz
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Transmit-Receive Test Setup
External 4GHz IF Amplifier
Received Eye
RX Antenna (25dBi)
Receiver Probe-station
Received Spectrum
~2m
PRBS Generator
TX Antenna (25dBi)
Transmitter Probe-station (not in shot)
Alexander Tomkins – University of Toronto
2008
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Transmit-Receive Test Results – 4Gb/s @ 50°C
RX
Data Transmission at 4 Gb/s (50°C)
0.6
0.1
0.5
0.4
0
0.3
0.2
-0.1
0.1
0
-0.2
-0.1
-0.2
-0.3
0
60.8GHz Carrier
5
10
15
20
time (ns)
25
30
35
TX
4.0Gbps 27-1 PRBS Signal
Transmitter @ 50°C, receiver @ room temperature
Alexander Tomkins – University of Toronto
2008
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Transmit-Receive Test Results – 6Gb/s
RX
0.6
0.1
0.5
0.4
0
0.3
0.2
-0.1
0.1
0
-0.2
-0.1
-0.2
-0.3
0
60.8GHz Carrier
5
10
time (ns)
15
20
25
TX
6.0Gbps 27-1 PRBS Signal
Testing limited by bandwidth of IF amplifier (4GHz)
Alexander Tomkins – University of Toronto
2008
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Summary
1.2V 60GHz zero-IF single-chip transceiver in 65nm CMOS
Occupies only 1.28x0.81mm2 (1.0mm2), consumes 374mW
Simple high-bandwidth, high data-rate architecture
Proof-of-concept demonstration: wireless link over 2m
Data-rates up to 6.0Gb/s demonstrated (IF bandwidth limited above 4GHz)
First demonstration of a 60GHz wireless link at 50oC
60GHz transceiver block characterization over process corners,
temperature, and power supply.
Alexander Tomkins – University of Toronto
2008
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Acknowledgements
This work was funded by Fujitsu Limited.
Many thanks to Katya Laskin and Ioannis Sarkas for testing,
measurement, and lab support.
The authors would like to thank Jaro Pristupa and CMC for CAD support,
CFI, OIT, and ECTI for test equipment.
We would also like to thank Dr. W. Walker of Fujitsu Laboratories of
America Inc. for his support.
Alexander Tomkins – University of Toronto
2008
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Backup
Alexander Tomkins – University of Toronto
2008
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60GHz SPST Switch (Stand-alone)
Tuned SPST switch for 60GHz operation
High-isolation from series-shunt transistor and 250pH inductor
Lower-insertion loss from 45pH shunt inductor
Alexander Tomkins – University of Toronto
2008
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Transmit-Receive Link Experiment
Goal: Demonstrate successful data transmission
“Bits in, bits out”
Single-ended input data stream (PRBS sequence) fed directly on-chip
Data stream reclaimed directly from the receiver IF output with no ADC
One probe-station will act as a transmitter, one as receiver
Transmit channel formed by:
2m wireless link with transmitter/receiver 25dBi horn antenna
Total channel loss (including input/output losses): 35dB
Lack of on-chip IF-amp requires an additional external amplifier (limited to
4GHz BW)
Alexander Tomkins – University of Toronto
2008
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Transmit-Receive Test Results
Data Transmission at 2 Gb/s (50°C)
0.6
0.1
0.5
0.4
0
0.3
0.2
-0.1
0.1
0
-0.2
-0.1
-0.2
-0.3
0
10
20
30
40
time (ns)
50
60
70
60.8GHz Carrier
2.0Gbps 27-1 PRBS Signal
Transmitter @ 50°C, receiver @ room temperature
Alexander Tomkins – University of Toronto
2008
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Comparison Table
Alexander Tomkins – University of Toronto
2008
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