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Ac test conditions – Rainbow Electronics DS1642 User Manual

Page 10

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DS1642

10 of 11

AC TEST CONDITIONS

Output Load:

100 pF + 1TTL Gate

Input Pulse Levels:

0.0 to 3.0 Volts

Timing Measurement Reference Levels:

Input: 1.5V
Output: 1.5V

Input Pulse Rise and Fall Times: 5 ns

NOTES:

1. 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.

5. Each DS1642 has a built–in switch that disconnects the lithium source until V

CC

is first applied by the

user. The expected t

DR

is defined as a cumulative time in the absence of V

CC

starting from the time

power is first applied by the user.

6. 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 to prevent damage to the crystal.