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Raltron Electronics Corporation 10651 NW 19th St. Miami, Florida 33172 U.S.A.
Tel: 305-593-6033 Fax: 305-594-3973 e-mail: sales@raltron.com Internet: http://www.raltron.com
TUNING FORK CRYSTAL UNITS
SERIES R38, R26, AND R145
3 x 8, 2 x 6, 1 x 5 mm
COMMON FREQUENCIES ARE: 31.250 kHz, 31.500 kHz, 40.00 kHz, AND 76.800 kHz
FREQUENCY DEVIATION AT T IS GIVEN AS:
f/f = K(To - T)2, WHERE K IS PARABOLIC CURVATURE CONSTANT
OTHER LOAD CAPACITANCES ARE AVAILABLE
OUTLINE DRAWINGS
R145
R26
.059 MAX
FEATURES
DESIGNED FOR TIME OF DAY CLOCKS APPLICATIONS
SMALL COMPACT SIZE WITH PERFORMANCE AND ECONOMY
EXCELLENT SHOCK AND ENVIRONMENTAL CHARACTERISTICS
SPECIFICATIONS
HOLDER TYPE
NOMINAL FREQUENCY
FREQUENCY TOLERANCE
TURNOVER TEMPERATURE
PARABOLIC CURVATURE
CONSTANT (TYP)
LOAD CAPACITANCE
EQUIVALENT SERIES
RESISTANCE (MAX)
DRIVE LEVEL (TYP)
MOTIONAL CAPACITANCE (TYP)
SHUNT CAPACITANCE (TYP)
CAPACITANCE RATIO (TYP)
AGING (FIRST YEAR MAX)
QUALITY FACTOR (TYP)
INSULATION RESISTANCE (MIN)
OPERATING TEMPERATURE
RANGE
STORAGE TEMPERATURE
RANGE
PART NUMBERING SYSTEM
R38
SERIES
FREQUENCY
LOAD
CAPACITANCE
TOLERANCE
EXTENDED
TEMPERATURE
R38
R26
R145
EXAMPLES:
R38-32.768-6-10PPM
R26-32.768-12.5-EXT
IN kHz
IN pF
±5 PPM
±10 PPM
EXT
( ±20 PPM ONLY)
-
-
-
-
SCALE NONE DIMENSION IN mm/INCH
R38
R26
R145
R38, R26
32.768 kHz
±5 ±10 ±20 PPM
25°C ±5°C
32.768 kHz
±5 ±10 ±20 PPM
25°C ±5°C
32.768 kHz
±5 ±10 ±20 PPM
25°C ±5°C
30.00 kHz TO 153.6 kHz
±5 ±10 ±20 PPM
25°C ±5°C
-0.034 PPM/C2
-0.034 PPM/C2
-0.034 PPM/C2
-0.034 PPM/C2
6 or 12.5 pF
6 or 12.5 pF
8.0 pF
6 or 12.5 pF
35k OHM
35k OHM
40k OHM
30k TO 50k OHM
1.0 μW
0.0035 pF
1.6 pF
460
±3 PPM
90000
500 M OHM
1.0 μW
0.003 pF
1.35 pF
450
±3 PPM
70000
500 M OHM
1.0 μW
0.0025 pF
1.0 pF
400
±3 PPM
80000
500 M OHM
1.0 μW
.001 TO .004 pF
0.8 TO 1.7 pF
425 TO 800
±5 PPM
FREQUENCY-PACKAGE SPECIFIC
500 M OHM
SHOCK RESISTANCE
STANDARD PART NUMBER
R38-32.768-12.5
R26-32.768-12.5
R145-32.768-12.5
SEE PART NUMBERING SYSTEM
±5 PPM MAXIMUM 75 cm DROP TEST IN 3 AXES ONTO A HARD SURFACE
OR 3000 g x 0.3 ms x SINEWAVE IN 3 AXES
-40°C TO +85°C
-20°C TO +60°C STANDARD
-40°C TO +85°C EXTENDED
3.10 MAX
.122 MAX
8
.
1
.
0.35 DIA
.014 DIA
1.10
.043
1.50 MAX
4
.
5
.
0.2 DIA
.008 DIA
0.45
.018
2.10 MAX
.083 MAX
6
.
5
.
0.70
.028
0.26 DIA
.010 DIA