euroquartz limited blacknell lane crewkerne somerset uk ta18 7he tel: +44 (0)1460 230000 fax: +44 (0)1460 230001 info@euroquartz.co.uk www.euroquartz.co.uk euro quartz 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 features designed for low power applications smallest available package in this frequency range hermetically sealed, ceramic package excellent ageing characteristics full military testing available packaging options cx4 crystals are available either tray packed (<250pcs) or tape and reel (>250 pieces). 16mm tape, 178mm or 330mm reels (eia 418). cx4 crystal how to order cx4 crystals cx4 - s - c - sm1 - 1.8432m, 500 / i 's' if special, custom design. otherwise leave blank blank = glass lid c = ceramic lid terminations sm1 = gold plated * sm2 = solder plated sm3 = solder dipped sm4 = solder plated * sm5 = solder dipped * * = lead free frequency k = khz m = mhz calibration tolerance @25c (in ppm) temp. range c = -10 ~ +70c i = -40 ~ +85c m = -55 ~ +125c s = customer specified sm1 1.14 1.27 sm2 1.17 1.30 sm3 1.22 1.35 sm4 1.17 1.30 sm5 1.22 1.35 glass lid ceramic lid dim. h ultra-miniature low profile smd parameters fundamental overtone frequency (hz): 600k 1.0m 1.4m 1.8432m 2.4576m motional resistance r1 (k): 300 400 600 500 1000 motional resistance r1 max. (k): 3k motional capacitance c1 (ff): 3.5 2.0 1.3 3.5 1.5 quality factor q (k): 250 200 150 80 45 shunt capacitance c0 (pf): 1.0 0.8 0.7 1.0 0.8 specifications stated are typical at 25c unless otherwise indicated. specifications may change without notice. 1. tighter tolerance available 2. other values available standard calibration tolerance 1 : 500ppm (0.5%) 1000ppm (0.1%) 10000ppm (1.0%) drive level: 3w maximum load capacitance cl 2 : 7pf turning point 2 : 35c temperature coefficient (k): -0.035ppm/c 2 note: frequency f at temperature t is related to frequency fo at turning point temperature to by: f-fo fo =k(t-to) 2 functional mode: extensional ageing, first year: 5pppm maximum shock, survival: 1500g, 0.3ms, ? sine vibration, survival: 20g rms, 10~2000hz random operating temperature range commercial: -10 to +70c industrial: -40 to +85c military: -55 to +125c storage temperature range: -55 to +125c maximum process temperature: +260c for 20 seconds fundamental mode: 600khz to 1.4mhz overtone: 1.8432mhz to 2.5mhz
euroquartz limited blacknell lane crewkerne somerset uk ta18 7he tel: +44 (0)1460 230000 fax: +44 (0)1460 230001 info@euroquartz.co.uk www.euroquartz.co.uk euro quartz crystal equivalent circuit r1 motional resistance l1 motional inductance c1 motional capacitance c0 shunt capacitance terminations - plating sm1 gold plated (lead free) sm2 solder plated sm3 solder dipped sm4 solder plated (lead free) sm5 solder dipped (lead free) designation termination 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 c d and c g provides the additional phase shift to sustain oscillation. the oscillation frequency (f o ) is 15 to 250ppm above the crystal's resonant frequency (f s ). drive level r a is used to limit the crystal's drive level by forming a voltage divider between r a and c d . r a also stabilizes the oscillator against changes in the amplifier's output resistance (r o ). r a 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 (c l ). c l is approximately equal to: note: c d and c g include stray layout-induced capacitance to ground and c s is the stray shunt capacitance between the crystal terminal. in practice, the effective value of c l will be less than that calculated from c d , c g and c s values because of the effect of the amplifier output resistance. c s should be minimized. the oscillation frequency (f o ) is approximately equal to: c l d g s c c c c c = x + d g + f o s 1 l = f + 2 (c o + c ) c 1 where f s = series resonant frequency of the crystal c 1 = motional capacitance c o = shunt capacitance conventional cmos pierce oscillator circuit cx4 crystal ultra-miniature low profile smd fundamental mode: 600khz to 1.4mhz overtone: 1.8432mhz to 2.5mhz
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