CX MINIATURE CRYSTALS EUROQUARTZ Telephone: +44(0)1460 230000 Fax: +44(0)1460 230001 Email: [email protected] Web: www.euroquartz.co.uk Page CX-1-SM 1 of 2 530kHz to 2.1MHz MINIATURE SMD CRYSTAL ! ! ! ! ! ! ! General Description The miniature CX-1-SM crystals in leadless ceramic packages have been designed for surface-mounting on printed circuit boards or hybrid circuits. Hermitically sealed in a rugged, miniature ceramic package, the CX-1-SM crystal is manufactured using a photolithographic process. Extensional mode Ideal for use with microprocessors 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 D (TO P) Frequency Range: Functional Mode: Calibration Tolerance*: 530kHz to 2 .1MHz Extensional A ±0.05% (±500ppm) B ±0.1% C ±1.0% 7pF Load Capacitance: 3kW max. Motional Resistance (R1): 1.2fF Motional Capacitance (C1): 150k Quality Factor (Q): 1.0pF Shunt Capacitance (C0): 3mW max. Drive Level: 35°C Turning Point (T0)**: Note: Frequency (f) deviation from frequency (f0) @ turning point temperature (T0): f-fo k(T-To)2 = fo A E D B C E Outline CX-1-SM Package Dimensions Dimension Typical (mm) Maximum (mm) A 8.00 8.38 B 3.56 3.94 C - see below D 1.14 1.40 E 1.52 1.78 Dimension “C” Glass Lid (mm max.) Ageing, first year: Shock, survival: Vibration, survival: Operating Temperature: Storage Temperature: Process Temperature: Ceramic Lid (mm max.) SM1 1.65 1.78 SM2 1.70 1.83 SM3 1.78 1.90 Specifications are typical at 25°C unless otherwise indicated. * ** Equivalent Circuit 1 L1 ±5ppm max. 750g 0.3ms, ½ sine 10g rms, 20-1,000Hz random -10°~+70°C (commercial) -40°~+85°C (industrial) -55°~+125°C (military) -55°C~+125°C 260°C for 20 seconds Tighter frequency calibration available Other turning point available Solder Pad Layout C1 R1 2 1.78 C0 4.06 6.86 L 1 Motional Inductance C 1 Motional Capacitance C0 Shunt Capacitance R 1 Motional Resistance CX MINIATURE CRYSTALS EUROQUARTZ Telephone: +44(0)1460 230000 Fax: +44(0)1460 230001 Email: [email protected] Web: www.euroquartz.co.uk Page CX-1-SM 530kHz to 2.1MHz MINIATURE SMD CRYSTAL 2 of 2 Circuit Design Conventional HCMOS Pierce Oscillator Circuit Typical Pierce Oscillator Application Rf Amplifier 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). CS C1 Drive Level CX-1 Buffer Osc. Freq. (Fo) RA C2 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. Terminations 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. Designation SM1 Gold Plated SM2 Nickel, Silver Plated SM3 Nickel, Solder Plated and Solder Dipped Packaging The oscillation frequency (f0) is approximately equal to: C1 f 0 = f S 1+ 2(C0 + CL ) Where FS = Series resonant frequency of the crystal C1 = Motional Capacitance C0 = Shunt Capacitance CX-1-SM - Tray Pack (Standard) - 16mm tape, 178mm or 330mm reels (Optional) per EIA 481 Order Code CX-1 Blank = Glass Lid C = Ceramic Lid “S” if special or custom design Blank if standard Frequency -SM1 1.0MHz SM1 SM2 SM3 Calibration Tolerance* @ 25°C (A) *For other (B) calibrations (C) insert value in ppm Termination (A / I) Temperature Range: C = Commercial I = Industrial M = Military S = Specify