11. Reference information
RX4111CE
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ETM62E-02
Seiko Epson Corporation
16
11. Reference information
11.1. Reference Data
(1)
Example of frequency and temperature characteristics
-150
-100
-50
0
-50
0
50
100
Temperature [
C]
Fr
e
q
u
e
n
c
y
f
T
10
-6
T
= +25
C Typ.
= -0.035
10
-6
Typ.
[
Finding the frequency stability
]
1.
Frequency and temperature characteristics can be
approximated using the following equations.
f
T
=
(
T
X
)
2
f
T
: Frequency deviation in any temperature
[1
/
C
2
]
: Coefficient of secondary temperature
(
0.035
0.005)
10
6
/
C
2
T
[
C]
: Ultimate temperature
(+25
5
C)
X
[
C]
: Any temperature
2.
To determine overall clock accuracy, add the
frequency precision and voltage characteristics.
f/f
=
f/fo
+
f
T
+
f
V
f/f
: Clock accuracy (stable frequency)
in any temperature and voltage.
f/fo
: Frequency precision
f
T
: Frequency deviation in any temperature.
f
V
: Frequency deviation in any voltage.
3.
How to find the date difference
Date Difference =
f/f
86400 (Sec)
For example:
f/f = 11.574
10
-6
is an error of
approximately 1 second/day.
Figure 18 Frequency vs Temperature characteristics
There is a tool on our web that makes it easy to calculate the time error due to temperature.
