DS1644/DS1644P

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NOTES:

1. All voltages are referenced to ground.

2. Typical values are at 25

°C and nominal supplies.

3. Outputs are open.

4. Data retention time is at 25

°C and is calculated from the date code on the device package. The date

code XXYY is the year followed by the week of the year in which the device was manufactured. For

7. Real-Time Clock Modules (DIP) can be successfully processed through conventional wave-soldering

techniques as long as temperatures 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 version:

a. Dallas Semiconductor recommends that PowerCap Module bases experience one pass through

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

b. Hand soldering and touch-up: Do not touch or apply the soldering iron to leads for more than

3 (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.