Real time clock module
High-Stability
I
2
C-Bus INTERFACE REAL TIME CLOCK MODULE
RX - 8025 SA
/
NB
•
Built-in 32.768 kHz quartz oscillator
:
Frequency adjusted for high accuracy
(
±
5
×
10
−
6
/ Ta = +25
°
C)
•
Interface Type
:
I
2
C-Bus Interface (400 kHz)
•
Operating voltage range
:
1.70 V to 5.5 V
•
Wide Timekeeper voltage range
:
1.15 V to 5.5 V
•
Various detection Functions
:
Ex. Oscillation stop detection function
•
Low backup current
:
0.48
µ
A / 3 V (Typ.)
Actual size
•
32.768 kHz frequency output function
:
C-MOS output With Control Pin
RX-8025SA
•
The various functions include full calendar, alarm, timer.
•
Lead(Pb)-free
:
Contains high melting temperature type solder (Pb85 %)
exempted by RoHS directive.
*
The I
2
C-Bus is a trademark of Philips Electronics N.V.
RX-8025NB
Block diagram
Alarm_W Register
( Min,Hour,Week )
Overview
•
Features built-in 32.768 kHz quartz oscillator
• Frequency adjusted for high accuracy.
(
±
5
×10
−6
/ Ta = +25
°C
)
( Equivalent to 13 seconds of monthly deviation )
FOUT
FOE
32 kHz
Output
Control
Comparator_W
Voltage
Detect
V
DD
Comparator_D
Alarm_D Register
( Min,Hour )
•
The various detection function
• Power supply voltage monitoring function
(with selectable detection threshold )
• Stop detection function
• Power-on reset detection function
OSC
Divider
Correc
-tion
Div.
Time Counter
( Sec,Min,Hour,Week,Day,Month,Year )
OSC
Detect
/ INTA
/ INTB
Address
Decoder
Address
Register
I/O
Control
•
Alarm function and Timer function
SCL
SDA
• Timer function produces a periodic interruption signal.
As for the Alarm function an optional combination is produced.
(Date of the week , time , minute)
Interrupt Control
Shift Register
GND
Pin Function
Signal
Name
SCL
SDA
FOUT
Input / output
Function
1.
2.
3.
4.
5.
6.
7.
Terminal connection / External dimensions
RX
−
8025 SA
1.27
(Unit:mm)
RX
−
8025 NB
0.5
Input
Serial clock input pin
Bi-directional
Data input and output pin
Output
FOUT pin is 32.768 kHz clock output pin
(C-MOS) that output control is possible.
FOE
input
L
H
/CLEN1
bit
X
0
0
1
1
/CLEN2
bit
X
0
1
0
1
FOUT
output
OFF ( LOW )
32.768 kHz
32.768 kHz
32.768 kHz
OFF(LOW)
N.C.
SCL
FOUT
N.C.
14.
10.1
±
0.2
N.C.
SDA
/ INTB
GND
/ INTA
N.C.
N.C.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
FOE
V
DD
(GND)
TEST
FOUT
SCL
SDA
/ INTB
GND
/ INTA
N.C.
5.0
±
0.2
22.
21.
6.3
Max.
N.C.
N.C.
N.C.
N.C.
N.C.
N.C.
N.C.
N.C.
N.C.
−
−
13.
12.
11.
20.
19.
18.
17.
FOE
/ INTA
/ INTB
TEST
V
DD
GND
Input
Output
Output
-
-
-
5.0
TEST
3.2
±
0.1
10.
9.
8.
4.8
16.
1.3
±
0.1
15.
14.
13.
12.
Interrupt output A pin ( N-ch open drain )
Interrupt output B pin ( N-ch open drain )
∗
Used by the manufacture for testing.
(Do not connect externally.)
Connected to a positive power supply.
Connected to a ground.
V
DD
FOE
7.4
±
0.2
SOP
−
14 pin
SON
−
22 pin
Metal may be exposed on the top or bottom of this product. This will not affect any quality, reliability or electrical spec.
Specifications (characteristics)
.
∗
Refer to application manual for details.
DC characteristics
T
a
=
−40 °C
to +85
°C
Recommended Operating Conditions
Item
Power voltage
Clock voltage
Operating
temperature
Symbol
V
DD
V
CLK
T
OPR
Condition
-
-
-
Min.
1.7
1.15
−40
Typ.
3.0
3.0
+25
Max.
5.5
5.5
+85
Unit
V
V
°C
Item
Symbol
I
BK
Condition
Min.
V
DD
=5V
V
DD
=3V
Typ.
0.60
0.48
Max.
1.80
Unit
µA
f
SCL
= 0Hz
Frequency characteristics
Item
Frequency
tolerance
Oscillation
start-up time
Frequency voltage
characteristics
∗1) ∗2)
Curent
Consumption
Condition
Range
AA: 5
±
5
AC: 0
±
5
1 Max.
±
1 Max.
∗1)
∗2)
Symbol
∆
f/f
Unit
×
10
−6
s
×
10
−6
I
32k
t
STA
f/V
T
a
= +25
°C
V
DD
= 3.0 V
T
a
= +25
°C
V
DD
= 2.0 V
T
a
= +25
°C
V
DD
= 2.0 V to 5.5 V
FOE = GND
FOUT ; output
OFF(LOW)
f
SCL
= 0Hz
V
DD
V
DD
, FOE = 5.5 V
= 5.5 V
FOUT ; output ON
( Output=OPEN;
CL = 0 pF )
1.20
3.0
6.5
µA
Power supply detection voltage
Item
High-voltage mode
Low-voltage mode
Symbol
V
DETH
V
DETL
Condition
V
DD
pin
V
DD
pin
Min.
1.90
1.15
T
a
=
−30 °C
to +70
°C
Typ.
2.10
1.30
Max.
2.30
1.45
Unit
V
V
Equivalent to 13 seconds of monthly deviation (excluding offset).
116
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