CX-2-SM31.0B

CX MINIATURE CRYSTALS 760kHz to 1.35MHz LOW-PROFILE SMD CRYSTAL EURO QUARTZ Telephone: +44(0)1460 230000 Fax: +44(0)1460 230001 Email: sales@euroquartz.co.uk Web: www.euroquartz.co.uk CX-2-SM CX-2-SM Page 1 of 2 General Description The miniature CX-2-SM quartz crystal is a high quality leadless device suitable for mounting on printed circuit boards or hybrid substrates. The CX-2-SM is hermetically sealed in a rugged, leadless ceramic package. The crystal has been designed for surface-mounting on printed circuit boards or hybrid circuits. The crystal is manufactured using a photo-lithographic process, yielding consistently high quality production parts.        Extensional mode High shock resistance Designed for low-power applications Compatible with hybrid or PC board packaging Low ageing Full military environmental testing available Ideal for battery operated applications Specification 760kHz to 1.35MHz Extensional A ±0.05% (±500ppm) B ±0.1% C ±1.0% 7pF Load Capacitance: 5kW max. Motional Resistance (R): 1.2fF Motional Capacitance (C): 150k Quality Factor (Q): 1.0pF Shunt Capacitance (C): 3mW max. Drive Level: 35°C Turning Point (T)**: Note: Frequency (f) deviation from frequency (f0) @ turning point temperature (T0): f-fo k(T-To) = fo -0.035ppm/°C2 Temperature Coefficient: ±5ppm max. Ageing, first year: 1000g 0.3ms, ½ sine Shock, survival: 10g rms, 20-1,000Hz random Vibration, survival: -10°~+70°C (commercial) Operating Temperature: -40°~+85°C (industrial) -55°~+125°C (military) -55°C~+125°C Storage Temperature: 260°C for 20 seconds Process Temperature: Specifications are typical at 25°C unless otherwise indicated. * ** Tighter frequency calibration available Other turning point available Frequency Range: Functional Mode: Calibration Tolerance*: 1 (TO P) A I G 2 H 3F D E B C Outline Terminal 1 is electrically connected to terminal 3 CX-2-SM Package Dimensions Dimension Typical (mm) Maximum (mm) A B C D E F G H I Dimension “C” 6.60 2.39 0.89 1.50 1.27 2.67 3.94 5.33 Glass Lid (mm max.) 6.99 2.74 see below 1.14 1.75 1.52 2.92 4.19 5.59 Ceramic Lid (mm max.) SM1 SM2 SM3 1.65 1.70 1.78 1.91 1.96 2.03 Equivalent Circuit L R 1 C C 2 Solder Pad Layout 2.67 2.87 1 2 0.6 R  Motional Resistance L  Motional Inductance C  Motional Capacitance C Shunt Capacitance CX MINIATURE CRYSTALS 760kHz to 1.35MHz LOW-PROFILE SMD CRYSTAL EURO QUARTZ Telephone: +44(0)1460 230000 Fax: +44(0)1460 230001 Email: sales@euroquartz.co.uk Web: www.euroquartz.co.uk CX-2-SM Page 2 of 2 Circuit Design Typical Pierce Oscillator Application The low profile CX miniature surface-mount crystal is ideal for small, battery operated portable products. The CX crystal design in a Pierce oscillator (single inverter) circuit has a very low current consumption with high stability. A conventional HCMOS Pierce oscillator circuit is shown below. The crystal is effectively inductive and in a Pi network with C1 and C2 which provides the additional phase-shift necessary to sustain oscillation. The oscillation frequency (f0) is 15ppm to 150ppm above the crystal’s series resonant frequency (FS). Conventional HCMOS Pierce Oscillator Circuit RB Amplifier Buffer Osc. Freq. (Fo) C5 R) Drive Level RA is used to limit the crystal’s drive level by forming a voltage divider between RA and C1. RA also stabilizes the oscillator against changes in the amplifiers output resistance (R0). RA should be increased for higher voltage operation. C CX-2 C 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: C x C2 CL = 1 C C1 + C2 + S NOTE: C1 and C2 include stray layout capacitance to ground. CS is the stray shunt capacitance between the crystal terminals. In practice, the effective valus of CL will be less than that calculated from C1, C2, and CS values due to the effect of the amplifier output resistance. CS should be minimized. The oscillation frequency (f0) is approximately equal to: f 0 = f S 1+ C1 2(C0 + CL ) Where FS = Series resonant frequency of the crystal C1 = Motional Capacitance C0 = Shunt Capacitance Terminations Designation Termination Packaging CX-2-SM Bulk Pack (Standard) - 16mm tape, 178mm or 330mm reels (Optional) per EIA 481 - Tray Pack (Optional) SM1 SM2 SM3 Gold Plated Nickel, Solder Plated Nickel, Solder Plated and Solder Dipped Order Code CX-2 C = Ceramic Lid Blank = Glass Lid Frequency -SM1 SM1 SM2 SM3 1.0MHz (A Calibration Tolerance* @ 25°C A, B, C / I ) “S” if special or custom design Blank if standard *For other calibration tolerances enter figure in ppm Temperature Range: C = Commercial I = Industrial M = Military S = Specify