CX-3-SM21.0A

CX MINIATURE CRYSTALS 800kHz to 1.35MHz LOW-PROFILE MINIATURE 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-3-SM CX-3-SM Page 1 of 2 General Description CX-3-SM quartz crystals are leadless devices designed for surfacemounting on printed circuit boards or hybrid circuits. Hermetically sealed in a rugged, ceramic package, the crystals are produced utilizing a photo-lithographic process giving excellent repeatability and consistent high quality.        Extensional mode Ideal for use with microprocessors Designed for low power applications Compatible with hybrid or PCB mounting Low ageing Full military environmental testing available Ideal for battery operated applications Specification 800kHz 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)**: -0.035ppm/°C2 Temperature Coefficient (k): Note: Frequency (f) deviation from frequency (f0) @ turning point temperature (t0) = f-fo k(T-To) = fo ±5ppm max. Ageing, first year: 1,000g peak, 0.3ms, ½ sine Shock: 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 Max. Process Temperature: Specifications are typical at 25°C unless otherwise indicated. * ** Closer frequency calibration available Other turning point available Frequency Range: Functional Mode: Calibration Tolerance*: D (TO P) A D D B C E Outline CX-3-SM Package Dimensions Dimension Typical (mm) Maximum (mm) A B C D E Dimension “C” 6.73 2.62 1.27 1.32 Glass Lid (mm max.) 7.11 2.90 see below 1.52 1.57 Ceramic Lid (mm max.) SM1 SM2 SM3 1.47 1.52 1.60 1.75 1.80 1.88 Equivalent Circuit Terminations 1 L C C R 2 Designation Termination SM1 SM2 SM3 Gold Plated Nickel, Silver Plated Nickel, Solder Plated and Solder Dipped L  Motional Inductance C  Motional Capacitance C Shunt Capacitance R  Motional Resistance CX MINIATURE CRYSTALS 800kHz to 1.35MHz LOW-PROFILE MINIATURE 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-3-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 designed 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 C CX-2 C 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. Solder Pad Layout 1.78 3.05 5.46 Load Capacitance The CX crystal calibration tolerance is influenced by the effective circuit capacitances, specified as the load capacitance (CL.) CL is 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: Packaging CX-3H-SM- Bulk Pack (Standard) - 16mm tape, 178mm or 330mm reels (Optional) per EIA 481 - Tray Pack (Optional) f 0 = f S 1+ C1 2(C0 + CL ) Where FS = Series resonant frequency of the crystal C1 = Motional Capacitance C0 = Shunt Capacitance Order Code CX-3 C = Ceramic Lid Blank = Glass Lid Frequency -SM1 SM1 SM2 SM3 1.0MHz (A / I ) “S” if special or custom design Blank if standard Calibration Tolerance* @ 25°C A, B, C *For other calibration tolerances enter figure in ppm Temperature Range: C = Commercial I = Industrial M = Military S = Specify