DS1286 Datasheet, PDF (14/18 Pages) Dallas Semiconductor – Watchdog Timekeeper

DS1284/DS1286
NOTES:
1. WE is high for a read cycle.
2. OE = V_IH or V_IL. If OE = V_IH during write cycle, the output buffers remain in a high-impedance state.
3. t_WP is specified as the logical AND of CE and WE. t_WP is measured from the latter of CE or WE going
low to the earlier of CE or WE going high.
4. t_DS or t_DH are measured from the earlier of CE or WE going high.
5. t_DH is measured from WE going high. If CE is used to terminate the write cycle, then t_DH = 20ns.
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.
9. Each DS1284/DS1286 is marked with a four-digit date code AABB. AA designates the year of
manufacture. BB designates the week of manufacture. The expected t_DR is defined as starting at the
date of manufacture.
10. All voltages are referenced to ground.
11. Applies to both interrupt pins when the alarms are set to pulse.
12. Interrupt output occurs within 100ns on the alarm condition existing.
13. RTC 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.
However, post-solder cleaning with water-washing techniques is acceptable, provided that ultrasonic
vibrations are not used to prevent crystal damage.
AC TEST CONDITIONS
Output Load: 100pF + 1TTL Gate
Input Pulse Levels: 0 to 3.0V
Timing Measurement Reference Levels
Input: 1.5V
Output: 1.5V
Input Pulse Rise and Fall Times: 5ns
PACKAGE INFORMATION
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
PACKAGE TYPE PACKAGE CODE DOCUMENT NO.
28 PDIP
P28+9
21-0044
28 PLCC
Q28+11
21-0049
28 EDIP
MDP28+1
21-0241
14 of 18