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Document Number: 35022
8
Revision: 17-Jun-05
XT38P
Vishay Dale
Miniature SMD Watch Crystal
FEATURES
2.5 mm height
Industry standard footprint
Long term stability
Tape and reel, 3000 pcs
100 % Lead (Pb)-free and RoHS compliant
The XT38P is a 2.5 mm height plastic molded 32.768 KHz
SMD crystal unit. This thermoplastic molded rugged part is
perfect for your SMD applications in limited circuit space
using the watch frequency.
DIMENSIONS in inches [millimeters]
PARABOLIC TEMPERATURE CURVE
To determine frequency stability, use parabolic curvature (k).
For example: What is stability at 45 C?
1) Change in Temperature (C) = 45 - 25 = 20 C
2) Change in Frequency = - 0.042 ppm*(
C)
= - 0.042 ppm*(20)
2
= - 16.8 ppm(max)
STANDARD ELECTRICAL SPECIFICATIONS
PARAMETER
SYMBOL
CONDITION
UNIT
MIN
TYPICAL
MAX
Frequency Range
F
O
KHz
32.768
Frequency Tolerance
F/F
O
at 25 C
ppm
-20
+20
Frequency Coefficient
K
parabolic coefficient
ppm/C
2
-0.027
-0.035
-0.043
Operating Temperature Range
T
OPR
C
-40
+85
Storing Temperature Range
T
STG
C
-55
+125
Shunt Capacitance
C
O
pF
1.0
Motional Capacitance
C
1
fF
2.0
Load Capacitance
CL
pF
12.5
Insulation Resistance
IR
M
500
Drive Level
DL
W
1.0
Aging (first year)
Fa
at 25 C 3 C
ppm
3.0
Equivalent Series Resistance(ESR)
Rs
K
50
ORDERING INFORMATION
XT38P
MODEL
A
PAD LAYOUT
32.768 KHz
FREQUENCY/KHz
e6
JEDEC Lead
(Pb)-Free
STANDARD
#1
#2
#4
#3
0.45
0.08
[1.15
0.2]
0.146
[3.7]
Max.
0.020
0.04
[0.5
0.1]
0.343 [8.7] Max.
0.45
0.08
[1.15
0.2]
0.098
[2.5]
Max.
XT38PA
0.217
0.04
[5.5
0.1]
- 20
- 10
0
10
20
30
40
50
60
70
- 10
- 20
- 30
- 40
- 50
- 60
F/f(ppm)
TEMPERATURE (
C)
GLOBAL PART NUMBER
MODEL
PAD
PACKAGE
FREQUENCY
LAYOUT
CODE
X
T
3
8
P
A
2
K
7
6
8
A
3
RoHS
COMPLIANT
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