EURO QUARTZ CX1SM CRYSTAL Miniature SMD Crystal for Pierce Oscillators 530kHz to 2.1MHz FEATURES Extensional Mode Ideal for use with microprocesors Designed for low power applications Full military testing available Low ageing OUTLINE & DIMENSIONS DESCRIPTION CX1SM crystals are leadless devices designed for surface mounting.the crystals are hermetically sealed in a rugged, ceramic package. CX1SM is intended for use in Pierce (single inverter) oscillator circuits. SPECIFICATION Specifications stated are typical at 25°C unless otherwise indicated. Specifications may change without notice. Parameters Fundamental Overtone Frequency Range (Hz): 555k 614k 1.0M 1.4M 1.8432 2.1M Motional Resistance R (Ω): 600 275 500 775 300 475 Motional Resistance R1 (max.) 3kΩ Motional Capacitance C1 (fF): 2.5 3.6 2.0 1.5 2.8 2.6 QualityFactor Q (k): 170 260 190 100 110 70 Shunt Capacitance C0 (pF): 1.2 1.3 1.1 1.0 1.3 1.3 Calibration Tolerance*: ±500ppm (0.05%) ±1000ppm (0.1%) ±10000ppm (1.0%) 3.0µW max. 7pF 35°C -0.035ppm/°C2 Drive Level: Load Capacitance**: Turning Point (T0)**: Temperature Coefficient (k): DIMENSION 'H' Note: Frequency f at temperature T is related to frequency F0 at turning point temperature To by: f-fo =k(T-To)2 fo Function Mode: Extensional Ageing, first year: 5ppm max. Shock, survival: 750g, 0.3ms, ½ sine Vibration, survival: 10g rms, 20~2000Hz random Operating Temperature Range Commercial: -10° to +70°C Industrial: -40° to +85°C Military: -55 to +125°C Storage Temperature Range: -55° to +125°C Maximum Process Temperature: +260°C for 20 seconds * ** Tighter tolerances are available. Other values are available Terminations SM1 SM2/SM4 SM3/SM5 Glass Lid Ceramic Lid 1.65 1.70 1.78 1.78 1.83 1.90 TERMINATIONS - PLATING Designation SM1 SM2 SM3 SM4 SM5 Termination Gold Plated (Lead Free) Solder Plated Solder Dipped Solder Plated (Lead Free) Solder Dipped (Lead Free) HOW TO ORDER CX1SM CRYSTALS CX1 - S - 'S' if special, custom design. Otherwise leave blank C Blank = glass lid C = ceramic lid - SM1 - Terminations SM1 = Gold plated * SM2 = Solder plated SM3 = Solder dipped SM4 = Solder plated * SM5 = Solder dipped * * = Lead free 1.0M 500 Frequency K = kHz M = MHz Calibration Tolerance @25°C (in ppm) / I Temp. Range C = -10° ~ +70°C I = -40° ~ +85°C M = -55° ~ +125°C S = Customer specified EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 [email protected] www.euroquartz.co.uk EURO QUARTZ CX1SM CRYSTAL Miniature SMD Crystal for Pierce Oscillators 530kHz to 2.1MHz CONVENTIONAL CMOS PIERCE OSCILLATOR CIRCUIT CRYSTAL EQUIVALENT CIRCUIT R1 Motional Resistance C1 Motional Capacitance L1 Motional Inductance C0 Shunt Capacitance PACKAGING OPTIONS CX1SM crystals are available either tray packed (<250pcs) or tape and reel (>250 pieces). 16mm tape, 178mm or 330mm reels (EIA 418). TYPICAL APPLICATION FOR A PIERCE OSCILLATOR The low profile CX miniature crystal is ideal for use in small, high density, battery operated portable products. The CX crystal designed in a Pierce oscillator (single inverter) circuit provides very low current consumption and high stability. A conventional Pierce oscillator is shown above. The crystal is effectively inductive and in a Pi network circuit with CD and CG provides the additional phase shift to sustain oscillation. The oscillation frequency (fO) is 15 to 250ppm above the crystal's resonant frequency (fS). Drive Level RA is used to limit the crystal's drive level by forming a voltage divider between RA and CD. RA also stabilizes the oscillator against changes in the amplifier's output resistance (RO). RA should be increased for higher voltage operation. Load Capacitance The CX crystal calibration tolerance is influenced by the effective circuit capacitances, specified as the load capacitance (CL). CL is approximately equal to: CL = CD x CG CD + CG + CS Note: CD and CG include stray layout-induced capacitance to ground and CS is the stray shunt capacitance between the crystal terminal. In practice, the effective value of CL will be less than that calculated from CD, CG and CS values because of the effect of the amplifier output resistance. CS should be minimized. The oscillation frequency (fO) is approximately equal to: fO = fS 1+ C1 2(C O + C L ) Where FS = Series resonant frequency of the crystal C1 = Motional Capacitance CO = Shunt Capacitance EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 [email protected] www.euroquartz.co.uk