RA4803SA
Page - 2
ETM38E-03
3. Terminal description
3.1. Terminal connections
RA4803
SA
1. CE
14. D I
2. CLK
13. DO
3. FOUT
12. T2 (V
PP
)
4. N.C.
11. GND
5. TEST
10. / INT
6. V
DD
9. EVIN
7. FOE
8. N.C.
SOP
−
14pin
3.2. Pin Functions
Signal
name
I/O
Function
CE
Input
This is the chip enabled input pin. It has a built-in pull-down resistance.
When the CE pin is at the "H" level, access to this RTC becomes possible. Also, when the
chip is not selected, the DO pin is at the high impedance level, and the CLK and DI pins
would not accept input.
CLK
Input
This is the shift clock input pin for serial data transfer.
In the write mode, it takes in data from the DI pin using the CLK signal rise edge.
In the read mode, it outputs data from the DO pin using the fall edge.
D I
Input
This is the data input pin for serial data transfer.
DO
Output
This is the data output pin for serial data transfer.
FOUT
Output
This is the C-MOS output pin with output control provided via the FOE pin.
When FOE =
"H"
(high level), this pin outputs a 32.768 kHz signal.
When output is stopped, the FOUT pin = "Hi-Z"( high impedance ).
FOE
Input
This is an input pin used to control the output mode of the FOUT pin.
When this pin's level is high, the FOUT pin is in output mode. When it is low, output via the
FOUT pin is stopped.
/ INT
Output
This pins is used to output alarm signals, timer signals, time update signals, and other
signals. This pin is an open drain pin.
EVIN
Input
External event input pin.
V
DD
−
This pin is connected to a positive power supply.
GND
−
This pin is connected to a ground.
TEST
Input
Use by the manufacture for testing. ( Do not connect externally.)
T2(V
PP
)
−
Use by the manufacture for testing. ( Do not connect externally.)
N.C.
−
This pin is not connected to the internal IC.
Leave N.C. pins open or connect them to GND or V
DD
.
Note: Be sure to connect a bypass capac
itor rated at least 0.1 μF between V
DD
and GND.
