Epson RTC-9701JE, Руководство по применению

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RTC - 9701 JE
MQ - 362 - 03
Page-19
15. Reference data
[Finding the frequency stability]
1. Frequency and temperature characteristics can be
approximated using the following equations.
∆
f
T
=
α
(
θ
T
-
θ
X
)
2
∆
f
T
: Frequency deviation in any
temperature
α
(1 /
°
C
2
) : Coefficient of secondary temperature
(
−
0.035
±
0.005)
×
10
-6
/
°
C
2
θ
T
(
°
C) : Ultimate temperature (+25
±
5
°
C)
θ
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 (seconds)
* For example:
∆
f/f = 11.574
×
10
-6
is an error of
approximately 1 second/day.
(1) Example of frequency and temperature characteristics
-150
-100
-50
0
-50 0 +50 +100
Temperature [
°
C]
F
re
que
nc
y
∆
f
T
×
10
-6
θ
T
= +25
°
C Typ.
α
= -0.035
×
10
-6
Typ.
(2) Example of frequency and voltage characteristics
- 3
2
F
req
uenc
y
∆
f
v
×
10
−
6
+ 3
0
3 4 5
Condition :
V
DD
=3 V
3 V as reference, Ta=+25
°
C
Supply Voltage V
DD2
[V]
(3) Current and voltage consumption characteristics
(3-1) V
DD
Current consumption (I
DD1
, I
DD2
)
2.5
2.0
1.0
3.0
3.5 4.0
I
DD1
: Output=OFF
C
u
rr
e
nt
con
s
um
pt
io
n
[
µ
A]
Condition :
Ta = +25
°
C
CE = GND
CL = 0 pF
V
DD2
= 3.0V
Supply Voltage V
DD
[V]
I
DD2
: Output=ON
(3-2) V
DD2
Current consumption (I
BK1
, I
BK2
)
2.0
C
u
rr
e
nt
con
s
um
pt
io
n
[
µ
A]
Supply Voltage V
DD2
[V]
2.0
1.0
3.0 4.0 5.0
Condition :
Ta = +25
°
C
FOUT ; Output ON or OFF
I
BK1
,I
BK2