Datenblatt

CX2SM CRYSTAL
760 kHz to 1.35 MHz
Low Profile Miniature
Surface Mount Quartz Crystal
DESCRIPTION
The CX2SM quartz crystals are leadless devices designed
for surface mounting on printed circuit boards or hybrid
substrates. They are hermetically sealed in a rugged,
miniature ceramic package. They are manufactured using
the STATEK-developed photolithographic process, and
were designed utilizing the experience acquired by
producing millions of crystals for industrial, commercial,
military and medical applications. Maximum process
temperature should not exceed 260O C.
actual size
side view
Glass Lid Shown
PACKAGE DIMENSIONS
B
1
FEATURES
Extensional mode
2
Ideal for use with microprocessors
Designed for low power applications
G
Compatible with hybrid or PC board
A
I
3
H
F
Low aging
Full military testing available
D
Ideal for battery operated applications
E
C
Designed and manufactured in the USA
TYP.
EQUIVALENT CIRCUIT
C0
1
L1
C1
R1
2
R1 Motional Resistance L1 Motional Inductance
C1 Motional Capacitance C0 Shunt Capacitance
SUGGESTED LAND PATTERN
0.113
(2.87)
0.060 (1.52)
inches (mm)
GRID
COURTYARD
1
DIM
inches
mm
inches
mm
A
0.260
6.60
0.275
6.99
B
0.094
2.39
0.108
2.74
C
-
-
D
0.035
0.89
0.045
1.14
E
0.059
1.50
0.069
1.75
see below
F
0.050
1.27
0.060
1.52
G
0.105
2.67
0.115
2.92
H
0.155
3.94
0.165
4.19
I
0.210
5.33
0.220
5.59
DIM “C”
0.105 (2.67)
MAX.
GLASS LID
CERAMIC LID
MAX
inches
mm
inches
mm
SM1
0.065
1.65
0.075
1.91
SM2/SM4
0.067
1.70
0.077
1.96
SM3/SM5
0.070
1.78
0.080
2.03
Note: Terminal 1 is electrically connected internally to terminal 3
2
0.060 (1.52)
10135 - Rev C
STATEK CORPORATION 512 N. MAIN ST., ORANGE, CA 92868 714-639-7810 FAX: 714-997-1256 www.statek.com
TYPICAL APPLICATION
FOR A PIERCE OSCILLATOR
SPECIFICATIONS
Specifications are typical at 25OC unless otherwise noted.
Specifications are subject to change without notice.
Frequency Range
760 kHz - 1.35 MHz
Functional Mode
Extensional
+
1
_ 500 ppm (0.05%)
Calibration Tolerance
+
_ 1000 ppm (0.1%)
+
_ 10000 ppm (1.0%)
Load Capacitance
7 pF
Motional Resistance (R1)
5 kΩ MAX
Motional Capacitance (C1) 1.2fF
Quality Factor (Q)
150 k
Shunt Capacitance (C0)
1.0 pF
Drive Level
3 µW MAX
2
Turning Point (T0)
35OC
Temperature Coefficient (k) -0.035 ppm/OC2
Aging, first year
5 ppm MAX
Shock, survival
1000 g, 0.3 ms,1/2 sine
Vibration, survival
10 g RMS, 20-1,000 Hz random
Operating Temp. Range
-10OC to +70OC (Commercial)
-40OC to +85OC (Industrial)
-55OC to +125OC (Military)
Storage Temp. Range
-55OC to +125OC
Max Process Temperature 260OC for 20 sec.
Note: Frequency f at temperature T is related to frequency f0
at turning point temperature T0 by: f-f0
2
= k(T-T0)
f0
The low profile CX miniature surface mount crystal is ideal
for 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 CMOS Pierce oscillator
circuit is shown below. The crystal is effectively inductive
and in a PI-network circuit with CD and CG provides the
additional phase shift necessary to sustain oscillation. The
oscillation frequency (f0) is 15 to 150 ppm above the
crystal’s series 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 amplifiers output
resistance (R0). 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 =
[
f0 = fS 1 +
Termination
Gold Plated
Solder Plated
Solder Dipped
Solder Plated (Lead Free)
Solder Dipped (Lead Free)
(1)
+ CS
The oscillation frequency (f0) is approximately equal to:
TERMINATIONS
Where f
S
C1
C0
C1
2(C0 + CL)
]
(2)
= Series resonant frequency of the crystal
= Motional Capacitance
= Shunt Capacitance
CONVENTIONAL CMOS
PIERCE OSCILLATOR CIRCUIT
Rf
PACKAGING OPTIONS
CX2SM
CD + CG
NOTE: CD and CG include stray layout 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.
1. Tighter frequency calibration available.
2. Other turning points available.
Designation
SM1
SM2
SM3
SM4
SM5
CD x CG
- Tray Pack
BUFFER
-16mm tape, 7” or 13” reels
(Reference tape and reel data sheet 10109)
AMPLIFIER
HOW TO ORDER CX2SM CRYSTALS
CX2
S
C
Blank = Glass Lid
C = Ceramic Lid
“S” if special or
custom design.
Blank if Std.
SM1
1.0M
,
500
Frequency
K = kHz
M = MHz
SM1 = Gold Plated (Lead Free)
SM2 = Solder Plated
SM3 = Solder Dipped
SM4 = Solder Plated (Lead Free)
SM5 = Solder Dipped (Lead Free)
Calibration
Tolerance
@ 25OC
(in ppm)
/
RA
OSC
Freq (fO )
I
Operating Temp. Range:
C = -10OC to +70OC
I = -40OC to +85OC
M = -55OC to +125OC
S = Customer Specified
CG
CX2
CD
STATEK CORPORATION 512 N. MAIN ST., ORANGE, CA 92868 714-639-7810 FAX: 714-997-1256 www.statek.com
10135 - Rev C
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