DS1556P Maxim Integrated Products, Inc., DS1556P Datasheet - Page 17

• Manufacturer Part Number: DS1556P
• Description: 1m, Nonvolatile, Y2k-compliant Timekeeping Ram
• Manufacturer: Maxim Integrated Products, Inc.

AC TEST CONDITIONS
Output Load: 50 pF + 1TTL Gate
Input Pulse Levels:
Timing Measurement Reference Levels:
Input Pulse Rise and Fall Times: 5 ns
NOTES:
1. Voltage referenced to ground.
2. Typical values are at +25°C and nominal supplies.
3. Outputs are open.
4. Battery switchover occurs at the lower of either the battery voltage or V
5. The IRQ/FT and RST outputs are open drain.
6. Data-retention time is at +25°C.
7. Each DS1556 has a built-in switch that disconnects the lithium source until V
8. RTC modules (DIP) can be successfully processed through conventional wave-soldering techniques
9. t
10. t
user. The expected t
absence of V
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.
In addition, for the PowerCap:
a. Dallas Semiconductor recommends that PowerCap Module bases experience one pass through
b. Hand soldering and touch-up: Do not touch or apply the soldering iron to leads for more than
AH1
AH2
Input: 1.5V
Output: 1.5V
solder reflow oriented with the label side up (“live-bug”).
3 seconds. To solder, apply flux to the pad, heat the lead frame pad and apply solder. To remove
the part, apply flux, heat the lead frame pad until the solder reflow and use a solder wick to
remove solder.
, t
, t
DH1
DH2
are measured from WE going high.
are measured from CE going high.
CC
starting from the time power is first applied by the user.
DR
is defined for DIP modules and PowerCap modules as a cumulative time in the
0.0 to 3.0V
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DS1556 1M, Nonvolatile, Y2K-Compliant Timekeeping RAM
PF
.
CC
is first applied by the