Rainbow Electronics DDS1693 User Manual
Page 30
DS1689/DS1693
30 of 32
NOTES:
1. All voltages are referenced to ground.
2. Typical values are at 25
°C and nominal supplies.
3. Outputs are open.
4. Value for voltage and currents is from the V
CCI
input pin to the V
CCO
pin.
5. Write protection trip point occurs during power fail prior to switchover from V
CC
to V
BAT
.
6. Value for voltage and currents is from the V
BAT
input pin to the V
CCO
pin.
7. Applies to the AD0-AD7 pins, and the SQW pin when each is in a high impedance state.
8. The
IRQ
pin is open drain.
9. Measured with a load of 50 pF + 1 TTL gate.
10. Wakeup kickstart timeout generated only when the oscillator is enabled and the countdown chain is
not reset.
11. V
SW
is determined by the larger of V
BAT
and V
BAUX
.
12. Z
CE
is an average input to output impedance as the input is swept from GND to V
CCI
and less than
4 mA is forced through Z
CE
.
13. The DS1693 will keep time to an accuracy of
±1 minute per month during data retention time for the
period of t
DR
.
14. t
DR
is the amount of time that the internal battery can power the internal oscillator and internal
registers of the DS1693. As such, t
DR
is specified with V
CCO
floating. If V
CCO
is powering an external
SRAM, an auxiliary battery must be connected to the V
BAUX
pin. The auxiliary battery should be sized
such that it can power the external SRAM for the t
DR
period.
15. The
CEI
pin has an internal pull-up of 60 k
W.
16. The PSEL pin has an internal pull-down of 60 k
W.
17. For industrial grade parts, I
BAT
(with OSC off) limit increases to 250 nA.
18. Real-Time Clock 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, provided that
ultrasonic vibration is not used.