a high-gain, low-noise, +6dbm pa in 90nm cmos for 60-ghz radio mehdi khanpour +, sorin voinigescu +,...
Post on 02-Jan-2016
215 Views
Preview:
TRANSCRIPT
A High-Gain, Low-Noise, +6dBm PA in 90nm CMOS for 60-GHz
Radio
Mehdi Khanpour+, Sorin Voinigescu+, M. T. Yang*+University of Toronto, *TSMC
October 2007
Compound Semiconductor IC Symposium
October 2007 Mehdi Khanpour 2
Outline
• Motivation
• 60-GHz Radio
• PA schematic
• Fabrication
• Measurement results
• Conclusion
October 2007 Mehdi Khanpour 3
Motivation
• 60-GHz Band (57-64 GHz)– Large bandwidth and limited propagation– High data rate (4+Gbps), short range– Personal Area Networks, Wireless HDTV
• CMOS alternative – lower power – higher integration and lower cost
October 2007 Mehdi Khanpour 4
60-GHz Radio
• Simple narrow-band radio architecture
• Implemented in 90nm CMOS– Receiver w/o VCO [1] – Up-converter [2]– Power Amplifier (this
work)
PLL
VCO
IFLNA
BUF
BUF
BUF
56-61 GHz
52.2-57.5 GHz
32
2 GHz
Reference
3.5-5.5 GHz
PA
56-61 GHz
3.5-5.5 GHzIF
October 2007 Mehdi Khanpour 5
PA Schematic
• Input designed as LNA with inductive feedback• Input matched by LG and LS
• Output designed as PA with source degeneration for linearitySGSTIN RRLfZ 2}{
October 2007 Mehdi Khanpour 6
PA Design
• Stage 1 biased at 0.2 mA/μm and sized for simultaneous noise and input impedance matching
• Stage 2 and 3 biased at 0.3 mA/μm for linearity
• Output stage sized for PSAT = 6.5 dBm with Inductive degeneration for linearity
• Inductors and interconnects modeled using ASITIC
October 2007 Mehdi Khanpour 7
Fabrication
• Fabricated in TSMC 90nm GP CMOS• 9-layer Cu back-end, no “thick” metal
67GHz Cable
110GHz Cable
67GHz Infinity Probes
50GHz Bias T
300μm× 500μm
Large signal test setup:
October 2007 Mehdi Khanpour 8
Simulations
• 18 dB Gain, 4.5 dB NF• Γopt, S11 and S22 < -10 dB from 50-68 GHz
October 2007 Mehdi Khanpour 9
Measurement vs. Simulation
• 14 dB Gain, 3dB bandwidth extends from 48-61 GHz• S11 and S22 < -10 dB from 48-65 GHz
October 2007 Mehdi Khanpour 10
Measurement vs. Simulation
• Measurement shows 14 dB gain @ 55 GHz
• Diffusion region in layout is wider than the minimum allowed by design kit
• Extra capacitance pushing the centre frequency down is not captured in simulations
56601
/1
MIN
D
WW
LCf
October 2007 Mehdi Khanpour 11
Measurement vs. Simulation
• S21 peaks at 55 GHz when extra capacitance is added
October 2007 Mehdi Khanpour 12
S-Parameters Across 5 Dies
• Results show excellent repeatability
October 2007 Mehdi Khanpour 13
S21 vs. Power Supply
• 2 dB drop in gain from 1.5V to 1.2V supply
October 2007 Mehdi Khanpour 14
Linearity Measurement
• 6 dBm PSAT, 1.6 dBm P1dB
• Maximum PAE is 6% @ 55 GHz and 5.2% @ 60 GHz, η = 22%
October 2007 Mehdi Khanpour 15
Linearity vs. Current Density
• Optimal linearity bias coincides with peak fT current density of 0.3~0.35 mA/μm
October 2007 Mehdi Khanpour 16
Temperature Measurements
• Gain decreases by 5 dB and PSAT by 2 dBm from 25oC to 100oC
October 2007 Mehdi Khanpour 17
Scaling
• Same concept implemented in 65nm at 80 GHz• Third stage is cascode with identical size (40 μm)• Higher gain but lower PSAT due to cascode output stage, η = 11%
October 2007 Mehdi Khanpour 18
PA Comparison
PA Technology
f G PSAT P1dB,out PAE Area Topology FoM
170 GHz fMAX 90nm
CMOS
60 GHz
14 dB 6 dBm 1.6 dBm 6% 0.3×0.5mm2 2-stage cascode + CS
10
170 GHz fMAX 90nm CMOS [3]
60 GHz
5.2 dB 9.3 dBm 6.4 dBm 7.4% 0.35×0.43mm2 3-stage CS 7.5
200/290 GHz fT/fMAX
SiGe HBT [4]
60 GHz
10.8dB 16 dBm 11.2 dBm 4.3% 2.1×0.8mm2 2-stage CE 73
200/290 GHz fT/fMAX
SiGe HBT [5]
77 GHz
19dB 14 dBm 12 dBm 15.7%
NA cascode + 2-stage CE
444
2fPAEGPFoM SAT
October 2007 Mehdi Khanpour 19
Conclusion
• 60-GHz PA with 14 dB gain demonstrated in 90nm CMOS
• PA characterized over process, supply voltage and temperature variation
• Results show excellent yield and repeatability
• Scalable to 80 GHz in 65nm CMOS
October 2007 Mehdi Khanpour 20
Acknowledgment
• Jaro Pristupa and CMC for CAD tools and support
• OIT and CFI for equipment grants
• TSMC for facilitating the technology access
October 2007 Mehdi Khanpour 21
References
[1] D. Alldred et al, CSICS 2006
[2] S. P. Voinigescu et al, ISCAS 2007
[3] T. Yao et al. RFIC-Symp 2006
[4] B. Floyd et al, ISSCC 2004
[5] S. T. Nicolson et al, IMS 2007
top related