Yang Lin and David E. Kotecki Electrical and Computer Engineering Department

1. A 0.8-13.4GHz combined differentialvoltage-controlled oscillator with an exclusive-OR in 130nm SiGeBiCMOS Yang Lin and David E. Kotecki Electrical and Computer Engineering Department University of Maine, USA 17th IEEE International Conference on Electronics, Circuits and Systems

2. Outline Wide-tuning voltage-controlled oscillator (VCO) applications Previous work on the state-of-the-art wide-tuning VCOs Design & Post-layout simulation of this work The differences between this design & previous presentation Lower power Smaller size Differential outputs 17th IEEE International Conference on Electronics, Circuits and Systems

3. Voltage-Controlled Oscillator (VCO) Differential VCO 17th IEEE International Conference on Electronics, Circuits and Systems

4. Wide-tuning VCO applications UWB Application (3.1-10.6GHz by Federal Communications Commission (FCC)) Communication Radar 17th IEEE International Conference on Electronics, Circuits and Systems

5. State-of-the-art wide-tuning VCOs Presentation 1 This work 17th IEEE International Conference on Electronics, Circuits and Systems

6. Architecture • For the XOR, • differential inputs Ap and An (0o delay @ frequency f0 ) • XOR differential inputs Bp and Bn (90o delay @ frequency f0) • = differential outputs Zp and Zn (frequency 2f0 ) • Base-collector-connected (level-shifting) NPN transistors: • decrease the XOR input voltages for Bp and Bn 17th IEEE International Conference on Electronics, Circuits and Systems

7. Ring VCO Ring VCO with differential delay cells Single-ended: odd delay cellsDifferential: odd/even delay cells N: number of delay cells Tp: propagation time through each delay cell Period T=2NTp 17th IEEE International Conference on Electronics, Circuits and Systems

8. Ring Quadrature VCO (QVCO) Delay cell • Gate width/length (µm) • Buffer: Common source (amplified output) • ‘Vctrl’ is high: low-frequency mode, T1 & T4 close to ‘off’, T2 & T3 • provide most currents • ‘Vctrl’ achieves a specific high value, the oscillation freq. keeps the same • ‘Vctrl’ is low: high-frequency mode, |Vgs| of T1 & T4 increases, • current and freq. boost • Increasing ‘Vdd’ boosts the output frequency 17th IEEE International Conference on Electronics, Circuits and Systems

9. BiCMOS Gilbert XOR Emitter followers as buffers Logic Part Current Source • Logic part, Emitter followers & Current source • Delays of Ap, An, Bp and Bn are 0o, 180o, 90o and 270o • Bp & Bn are ~0.7V lower than Ap & An • Zp and Zn are differential outputs • BiCMOS XOR outperforms CMOS XOR: high frequency & differential outputs • CMOS XOR: up to ~5.5GHz input freq. 17th IEEE International Conference on Electronics, Circuits and Systems

10. Microchip Layout QVCO 450µm XOR 450µm The ground & power planes are not shown for clarity. 17th IEEE International Conference on Electronics, Circuits and Systems

11. Post-layout simulation resultsOscillation Frequency 13.4GHz Tuning range = 177% 0.8GHz 17th IEEE International Conference on Electronics, Circuits and Systems

12. Max frequencies @ different temperatures 13.889GHz Temperature coefficient ~ -12.5MHz/oC 12.889GHz 17th IEEE International Conference on Electronics, Circuits and Systems

13. VCO transient differential outputs@13.4GHz into 50Ω loads •Non-ideally symmetrical 2nd-harmonic output signals • Peak-peak voltage amplitude ~30mV 17th IEEE International Conference on Electronics, Circuits and Systems

14. Output power spectrum into a 50Ω load 13.4 GHz, -30 dBm The rejections 29dB @6.5GHz 28dB @19.5GHz 19dB @26GHz @13.4 GHz, Dissipated power: 15.52 mW, Output power: -30 dBm @0.8 GHz, Dissipated power: 13.98 mW, Output power: -45 dBm 17th IEEE International Conference on Electronics, Circuits and Systems

15. Phase Noise (PN) versus offset frequency At 10MHz offset frequency, PN= -91.5 dBc/Hz @ 13.4GHz oscillation frequency PN= -100.1 dBc/Hz @ 0.8GHz oscillation frequency 13.4GHz oscillation frequency, -91.5 dBc/Hz @10MHz offset frequency 17th IEEE International Conference on Electronics, Circuits and Systems

16. Conclusions • A ring QVCO + An XOR • Tuning range : 0.8 to 13.4 GHz (177%) • Dissipated power: 15.52mW@13.4GHz, 13.98mW@0.8GHz Output power into 50 Ohm loads: -30dBm@13.4GHz, -45dBm@0.8GHz • Phase Noise : 10MHz offset frequency, -91.5 dBc/Hz @ 13.4GHz oscillation freq. -100.1 dBc/Hz @ 0.8GHz oscillation freq. • Microchip area : 450µm×450µm 17th IEEE International Conference on Electronics, Circuits and Systems

17. Comparison 17th IEEE International Conference on Electronics, Circuits and Systems

18. Thank you very much! 17th IEEE International Conference on Electronics, Circuits and Systems