DS1685/DS1687 3V/5V Real-Time Clocks
WAKE-UP/KICKSTART TIMING
*THIS CONDITION CAN OCCUR WITH THE 3V DEVICE.
NOTE: TIME INTERVALS SHOWN ABOVE ARE REFERENCED IN WAKE-UP/KICKSTART SECTION.
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
All voltages are referenced to ground.
Typical values are at +25°C and nominal supplies.
Outputs are open.
Applies to the AD0–AD7 pins and the SQW pin when each is in a high-impedance state.
The IRQ and PWR pins are open-drain outputs.
Measured with a load of 50pF + 1 TTL gate.
Wake-up kickstart timeout generated only when the oscillator is enabled and the countdown chain is not reset.
VSW is determined by the larger of VBAT and VBAUX
The DS1687 keeps time to an accuracy of ±1 minute per month at 25°C during data retention time for the period of tDR
.
.
Note 10: tDR is the amount of time that the internal battery can power the internal oscillator and internal registers of the DS1687
at 25°C.
Note 11: RTC Encapsulate DIP modules can be successfully processed through conventional wave-soldering techniques as
long as temperature exposure to the lithium energy source contained within does not exceed +85°C. Post solder
cleaning with water washing techniques is acceptable, if ultrasonic vibration is not used.
Note 12: IBAT1 and IBAT2 are measured at VBAT or VBAUX = 3.5V and with recommended crystal type on X1 and X2.
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DALLAS [ DALLAS SEMICONDUCTOR ]
