EURO QUARTZ CX4 CRYSTAL Ultra-miniature Low Profile SMD Fundamental Mode: 600kHz to 1.4MHz Designed for low power applications Overtone: 1.8432MHz to 2.5MHz Smallest available package in this frequency range FEATURES Hermetically sealed, ceramic package Excellent ageing characteristics Full Military testing available DESCRIPTION CX4 crystals are leadless devices designed for surface mounting on PCBs or hybrid substrates. The crystal has been designed for low power applications. OUTLINE & DIMENSIONS SPECIFICATION Specifications stated are typical at 25°C unless otherwise indicated. Specifications may change without notice. Parameters Fundamental Frequency (Hz): Motional Resistance R1 (kΩ): Overtone 600K 1.0M 1.4M 1.8432M 2.4576M 300 400 600 500 1000 1.5 Motional Resistance R1 Max. (kΩ): 3kΩ Motional Capacitance C1 (Ff): 3.5 2.0 1.3 3.5 Quality Factor Q (k): 250 200 150 80 45 Shunt Capacitance C0 (pF): 1.0 0.8 0.7 1.0 0.8 Standard Calibration Tolerance1: ±500ppm (±0.5%) ±1000ppm (±0.1%) ±10000ppm (±1.0%) 3µW maximum 7pF 35°C -0.035ppm/°C2 Drive Level: Load Capacitance CL2: Turning Point2: Temperature Coefficient (k): Note: Frequency f at temperature T is related to frequency Fo at turning point temperature To by: f-fo =k(T-To)2 fo Functional mode: Extensional Ageing, First year: ±5pppm maximum Shock, survival: 1500g, 0.3ms, ½ sine Vibration, survival: 20g rms, 10~2000Hz 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 1. 2. Dim. H Glass Lid Ceramic Lid SM1 SM2 SM3 SM4 SM5 1.14 1.17 1.22 1.17 1.22 1.27 1.30 1.35 1.30 1.35 PACKAGING OPTIONS Tighter tolerance available Other values available CX4 crystals are available either tray packed (<250pcs) or tape and reel (>250 pieces). 16mm tape, 178mm or 330mm reels (EIA 418). HOW TO ORDER CX4 CRYSTALS CX4 - 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 1.8432M, Frequency K = kHz M = MHz 500 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 CX4 CRYSTAL Ultra-miniature Low Profile SMD Fundamental Mode: 600kHz to 1.4MHz Overtone: 1.8432MHz to 2.5MHz CRYSTAL EQUIVALENT CIRCUIT R1 Motional Resistance C1 Motional Capacitance L1 Motional Inductance C0 Shunt Capacitance CONVENTIONAL CMOS PIERCE OSCILLATOR CIRCUIT 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: TERMINATIONS - PLATING Designation SM1 SM2 SM3 SM4 SM5 fO = fS Termination Gold Plated (Lead Free) Solder Plated Solder Dipped Solder Plated (Lead Free) Solder Dipped (Lead Free) 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