Rainbow Electronics DS1682 - Manual (Page 3)

DS1682
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SIGNAL DESCRIPTIONS
V
CC
– V
CC
is a +2.5V to +5.5V input supply.
GND – Ground.
SCL (2-Wire Serial-Clock Input) – The SCL pin is the serial-clock input for the 2-wire synchronous
communications channel. The SCL pin is an input that requires an external pullup resistor.
SDA (2-Wire Input/Output) – The SDA pin is the data input/output signal for the 2-wire synchronous
communications channel. The SDA pin is an open-drain I/O, which requires an external pullup resistor.
EVENT (Event Input) – The EVENT pin is the input the DS1682 monitors to determine when an event
occurs. When the pin is pulled high, the contents of the EEPROM are transferred to the ETC and the
oscillator starts. The ETC will begin to count in quarter-second increments. When the EVENT pin falls to
a logic 0, the event counter increments and the event counter, ETC, and user-memory data are stored in
the EEPROM array. When the EVENT pin changes states, the 2-wire bus is unavailable for
communications for t
EW
. The EVENT input is also deglitched (t
G
) to prevent short noise spikes from
triggering an event.
ALARM (Alarm Output) – The DS1682 monitors the values in the ETC for the programmed value in the
alarm register. When the ETC matches the alarm value, the alarm flag (AF) is set. Once set, the alarm
flag cannot be reset. See the operating descriptions for the AOS and AP bits for details about the
operation of the ALARM pin.
N/C (No Connect) – This pin is not connected internally.