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 CX3SM crystal low profile miniature smd at crystal 800khz to 1.35mhz description CX3SM crystals consist of a high quality extensional mode resonator in a rugged, hermetically sealed ceramic package. specifications stated are typical at 25c unless otherwise indicated. specifications may change without notice. frequency range: 800khz to 1.35mhz standard calibration tolerance*: 500ppm (0.05%) 1000ppm (0.1%) 10000ppm (1.0%) load capacitance: 7pf motional resistance (r1): 5k maximum motional capacitance (c1): 1.2ff quality factor (q): 150k shunt capacitance (c0): 1.0pf drive level: 3w maximum turning point (t0**): 35c temperature coefficient (k): -0.035ppm/c 2 ageing first year: 5ppm maximum shock, survival: 1000g, 0.3ms, ? sine vibration, survival: 10g rms, 20~1000hz random operating temperature range: -10c to +70c (commercial) -40c to +85c (industrial) -55c to +125c (military) storage temperature range: -55 to +125c maximum process temperature: +260c for 20 seconds specification features extensional mode resonator, 760khz to 1.35mhz designed for low power applications ideal microprocessor clock crystal low ageing full military testing available packaging options CX3SM crystals are available either tray packed (<250pcs) or tape and reel (>250 pieces). 16mm tape, 178mm or 330mm reels (eia 418). * tighter frequency calibration is available. ** other turning point is available. how to order CX3SM crystals cx3 - s - c - sm1 - 1.0m , 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 note: frequency f at temperature t is related to frequency fo at turning point temperature to by: f-fo fo =k(t-to) 2 turning point temperature sm1 1.35 1.70 sm2 1.40 1.75 sm3 1.47 1.83 sm4 1.40 1.75 sm5 1.47 1.83 glass lid ceramic lid dim. h outline & dimensions
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 CX3SM crystal low profile miniature smd crystal 800khz to 1.35mhz 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
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