DS1248/DS1248P

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AC TEST CONDITIONS

Output Load:

50pF + 1TTL Gate

Input Pulse Levels:

0V to 3V

Timing Measurement Reference Levels

Input:

1.5V

Output:

1.5V

Input Pulse Rise and Fall Times: 5ns

NOTES:

1) WE is high for a read cycle.

state.

going low to the earlier of CE or WE going high.

5) These parameters are sampled with a 50pF load and are not 100% tested.

6) If the CE low transition occurs simultaneously with or later than the WE low transition in Write

Cycle 1, the output buffers remain in a high impedance state during this period.

7) If the CE high transition occurs prior to or simultaneously with the WE high transition, the output

buffers remain in a high impedance state during this period.

8) If WE is low or the WE low transition occurs prior to or simultaneously with the CE low transition,

the output buffers remain in a high impedance state during this period.

running.

11) Voltages are referenced to ground.

12) RST (Pin 1) has an internal pullup resistor.

13) 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.

In addition, for the PowerCap:

1) Dallas Semiconductor recommends that PowerCap Module bases experience one pass through solder

reflow oriented with the label side up (“live-bug”).

2) Hand soldering and touch-up: Do not touch or apply the soldering iron to leads for more than three

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 reflows, and use a solder wick to remove

solder.