Data Sheet

EURO QUARTZ
CX3SM CRYSTAL
800kHz to 1.35MHz
Low Profile Miniature SMD AT Crystal
FEATURES
Extensional mode resonator, 760kHz to 1.35MHz
Designed for low power applications
Ideal microprocessor clock crystal
Low ageing
Full military testing available
OUTLINE & DIMENSIONS
DESCRIPTION
CX3SM crystals consist of a high quality extensional mode resonator
in a rugged, hermetically sealed ceramic package.
SPECIFICATION
Specifications stated are typical at 25°C 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):
5kΩ maximum
Motional Capacitance (C1):
1.2fF
Quality Factor (Q):
150k
Shunt Capacitance (C0):
1.0pF
Drive Level:
3µW maximum
Turning Point (T0**):
35°C
Temperature Coefficient (k):
-0.035ppm/°C2
Ageing First Year:
±5ppm maximum
Shock, Survival:
1000g, 0.3ms, ½ sine
Vibration, Survival:
10g rms, 20~1000Hz random
Operating Temperature Range:
-10°C to +70°C (Commercial)
-40°C to +85°C (Industrial)
-55°C to +125°C (Military)
Storage Temperature Range:
-55° to +125°C
Maximum Process Temperature:
+260°C for 20 seconds
*
**
Dim. H
Glass
Lid
Ceramic
Lid
SM1
SM2
SM3
SM4
SM5
1.35
1.40
1.47
1.40
1.47
1.70
1.75
1.83
1.75
1.83
PACKAGING OPTIONS
Tighter frequency calibration is available.
Other turning point is available.
CX3SM crystals are available either tray packed (<250pcs) or tape
and reel (>250 pieces).
16mm tape, 178mm or 330mm reels (EIA 418).
Turning Point Temperature
Note: Frequency f at temperature T is related to frequency Fo at
turning point temperature To by:
f-fo
=k(T-To)2
fo
HOW TO ORDER CX3SM CRYSTALS
CX3 -
S
'S' if special,
custom design.
Otherwise leave
blank
-
C
Blank = glass lid
C = ceramic lid
-
SM1
-
Terminations
SM1 = Gold plated *
SM2 = Solder plated
SM3 = Solder dipped
SM4 = Solder plated *
SM5 = Solder dipped *
* = Lead free
1.0M
Frequency
K = kHz
M = MHz
, 500
Calibration
Tolerance
@25°C
(in ppm)
/
I
Temp. Range
C = -10° ~ +70°C
I = -40° ~ +85°C
M = -55° ~ +125°C
S = Customer specified
EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE
Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 [email protected] www.euroquartz.co.uk
EURO QUARTZ
CX3SM CRYSTAL
800kHz to 1.35MHz
Low Profile Miniature SMD Crystal
CRYSTAL EQUIVALENT CIRCUIT
R1 Motional Resistance
C1 Motional Capacitance
L1 Motional Inductance
C0 Shunt Capacitance
CONVENTIONAL CMOS PIERCE OSCILLATOR CIRCUIT
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 CD and CG provides the additional phase shift to sustain
oscillation. The oscillation frequency (fO) is 15 to 250ppm above the
crystal's resonant frequency (fS).
Drive Level
RA is used to limit the crystal's drive level by forming a voltage divider
between RA and CD. RA also stabilizes the oscillator against changes in
the amplifier's output resistance (RO). RA 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 (CL). CL is
approximately equal to:
CL =
CD x CG
CD + CG
+ CS
Note: CD and CG include stray layout-induced capacitance to ground
and CS is the stray shunt capacitance between the crystal terminal. In
practice, the effective value of CL will be less than that calculated from
CD, CG and CS values because of the effect of the amplifier output
resistance. CS should be minimized.
The oscillation frequency (fO) is approximately equal to:
TERMINATIONS - PLATING
Designation
SM1
SM2
SM3
SM4
SM5
fO = fS
Termination
Gold Plated (Lead Free)
Solder Plated
Solder Dipped
Solder Plated (Lead Free)
Solder Dipped (Lead Free)
1+
C1
2(C O + C L )
Where
FS = Series resonant frequency of the crystal
C1 = Motional Capacitance
CO = Shunt Capacitance
EUROQUARTZ LIMITED Blacknell Lane CREWKERNE Somerset UK TA18 7HE
Tel: +44 (0)1460 230000 Fax: +44 (0)1460 230001 [email protected] www.euroquartz.co.uk
Similar pages