RTC4573 Epson Company, RTC4573 Datasheet - Page 10

• Manufacturer Part Number: RTC4573
• Description: Serial RTC with Alarm and Timer
• Manufacturer: Epson Company

n
( 1 ) Frequency temperature characteristics
Note : This data shows average values for a sample lot.
( 2 ) Frequency voltage characteristics
Reference data
-100
-110
-120
-10
-20
-30
-40
-50
-60
-70
-80
-90
Frequency[ppm]
10
+ 10
( typical )
0
- 10
For rated values, see the spacifications on page 3.
( typical )
+ 5
-40
- 5
0
-30
-20
a = -0.035ppm/°C² TYP.
-10
2
q
T
0
= 25°C TYP.
Temperature [°C]
10
Supply voltage V
Conditions
3
3V reference , Ta=+25°C
20
30
4
40
DD
5
50
[V]
60
70
Page-10
80
( 3 ) Current consumption voltage characteristics
Finding the frequency stability (clock error)
1. The frequency temperature characteristics can be
2. To determine the overall clock accuracy, add the
3. Finding the daily deviation:
approximated by using the following expression:
frequency tolerance and the voltage characteristics:
The clock error is one second per day at 11.574 ppm.
Daily deviation (seconds) = Df/f x 10
D f
a (ppm/
q
q
D f
D f
D
D
( typical )
T
X
f
f
Current consumption [µA]
T
(
(
/f
/f
T
V
Df
Df/f(ppm) = Df/f0 + Df
(ppm)
°C
°C
0
(ppm)
(ppm)
(ppm)
(ppm)
4
3
2
1
)
)
T
°C
(ppm)=a(q
2
)
: Frequency deviation at target temperature
: Secondary temperature coefficient
: Peak temperature
: Target temperature
: Clock accuracy at a given temperature
: Frequency tolerance
: Temperature dependent frequency
: Voltage dependent frequency deviation
and voltage
deviation
(-0.035 0.005ppm/
2
T
-q
Conditions
X
Ta=+25
)
CE0,CE1=0V,No load
2
3
T
(25
°C
Supply voltage V
+ Df
°C
2
°C
)
4
±
5
V
°C
)
5
-6
x 86400
DD
[V]
Aug.1998