J.Semicond.2010,31(7) Zhao Wei et al. Table 2.Performance comparisons. Parameter Ref.[1] Ref.[2] Ref.[3] This Work Frequency (MHz) 26 26 19.2 25 Application GSM/Bluetooth/WLAN WCDMA DVB tuner Phase noise 1 kHz (dBc/Hz) -140 -138 -137 -139 Supply voltage(V) 1.4 1.5 2.7 1.8 Tuning range(ppm) ~70 28 NA ≈35 Power consumption(mW) 4.2 6.5 1.8 Supply pushing(ppm/V) 0.2 ±2 Frequency instability at-10 to 55 C(ppm) ±4 2 <3 47 Die area(mm) 0.18 0.52 0.75 0.4 Technology 90 nm CMOS 0.13 um CMOS 0.35 um SiGe BiCMOS 0.18 um CMOS tude control loop is introduced to balance the phase noise per- [2]Tsai MD,Yeh CW,Cho YH,et al.A temperature-compensated formance and the power consumption.A 10-bit thermometer- low-noise digitally-controlled crystal oscillator for multi-standard code capacitor array with segmentally tapered capacitor size is applications.Proc IEEE Radio Frequency Integrated Circuits adopted to guarantee the monotonocity.The impedance boost (RFIC)Symp,sec.RTU4B-1,Atlanta,CA,Jun 2008:533 technique is employed to suppress the supply pushing.The [3]Farahvash S,Quek C,Mak M.A temperature-compensated measured phase noise is about-139 dBc/Hz at 1 kHz and digitally-controlled crystal Pierce oscillator for wireless applica- -151 dBc/Hz at 10 kHz frequency offset while it only draws 1 tions.ISSCC Dig Tech Papers,Feb 2008:352 mA from a 1.8 V supply.The measured supply pushing is+2 [4]Santos JT,Meyer RG.A one-pin crystal oscillator for VLSI cir- cuits.IEEE J Solid-State Circuits,1984,SC-19(2):228 ppm/V.Measurements show that this DCXO has a~35 ppm [5]Vittoz E,Degrauwe M,Bitz S.High performance crystal oscilla- tuning range with a~0.04 ppm frequency step.The DCXO tor circuits:theory and application.IEEE J Solid-State Circuits, with good phase noise and frequency stability can meet the re- 1988.23:774 quirements of tuner applications. [6]Lu L,Gong Z,Liao Y,et al.A 975-to-1960 MHz,fast-locking fractional-N synthesizer with adaptive bandwidth control and 4/4.5 prescaler for digital TV tuners.ISSCC Dig Tech Papers,Feb References 2009:396 [7]Lee T H.The design of CMOS radio-frequency integrated cir- [1]Lin J.A low-phase-noise 0.004-ppm/Step DCXO with guaranteed cuits.2nd ed.Cambridge,UK:Cambridge University Press,2004 monotonicity in the 90-nm CMOS process.IEEE J Solid-State [8]Lee T H,Hajimiri A.Oscillator phase noise:a tutorial.IEEE J Circuits,Dec 2005:2726 Solid-State Circuits,2000,35(3):326 075003-6J. Semicond. 2010, 31(7) Zhao Wei et al. Table 2. Performance comparisons. Parameter Ref. [1] Ref. [2] Ref. [3] This Work Frequency (MHz) 26 26 19.2 25 Application GSM/Bluetooth/WLAN WCDMA — DVB tuner Phase noise @ 1 kHz (dBc/Hz) –140 –138 –137 –139 Supply voltage (V) 1.4 1.5 2.7 1.8 Tuning range (ppm)  70  28 N.A  35 Power consumption (mW) 3 4.2 6.5 1.8 Supply pushing (ppm/V) 1 — 0.2 ˙2 Frequency instability at –10 to 55 ıC (ppm) ±4 2 < 3 ±7 Die area (mm2 ) 0.18 0.52 0.75 0.4 Technology 90 nm CMOS 0.13 μm CMOS 0.35 μm SiGe BiCMOS 0.18 μm CMOS tude control loop is introduced to balance the phase noise per￾formance and the power consumption. A 10-bit thermometer￾code capacitor array with segmentally tapered capacitor size is adopted to guarantee the monotonocity. The impedance boost technique is employed to suppress the supply pushing. The measured phase noise is about –139 dBc/Hz at 1 kHz and –151 dBc/Hz at 10 kHz frequency offset while it only draws 1 mA from a 1.8 V supply. The measured supply pushing is ˙2 ppm/V. Measurements show that this DCXO has a  35 ppm tuning range with a  0.04 ppm frequency step. The DCXO with good phase noise and frequency stability can meet the re￾quirements of tuner applications. References [1] Lin J. A low-phase-noise 0.004-ppm/Step DCXO with guaranteed monotonicity in the 90-nm CMOS process. IEEE J Solid-State Circuits, Dec 2005: 2726 [2] Tsai M D, Yeh C W, Cho Y H, et al. A temperature-compensated low-noise digitally-controlled crystal oscillator for multi-standard applications. Proc IEEE Radio Frequency Integrated Circuits (RFIC) Symp, sec. RTU4B-1, Atlanta, CA, Jun 2008: 533 [3] Farahvash S, Quek C, Mak M. A temperature-compensated digitally-controlled crystal Pierce oscillator for wireless applica￾tions. ISSCC Dig Tech Papers, Feb 2008: 352 [4] Santos J T, Meyer R G. A one-pin crystal oscillator for VLSI cir￾cuits. IEEE J Solid-State Circuits, 1984, SC-19(2): 228 [5] Vittoz E, Degrauwe M, Bitz S. High performance crystal oscilla￾tor circuits: theory and application. IEEE J Solid-State Circuits, 1988, 23: 774 [6] Lu L, Gong Z, Liao Y, et al. A 975-to-1960 MHz, fast-locking fractional-N synthesizer with adaptive bandwidth control and 4/4.5 prescaler for digital TV tuners. ISSCC Dig Tech Papers, Feb 2009: 396 [7] Lee T H. The design of CMOS radio-frequency integrated cir￾cuits. 2nd ed. Cambridge, UK: Cambridge University Press, 2004 [8] Lee T H, Hajimiri A. Oscillator phase noise: a tutorial. IEEE J Solid-State Circuits, 2000, 35(3): 326 075003-6