DS1557WP-120IND Maxim Integrated Products, DS1557WP-120IND Datasheet - Page 8

• Manufacturer Part Number: DS1557WP-120IND
• Description: IC RTC RAM Y2K 3.3V 120NS 34PCM
• Manufacturer: Maxim Integrated Products
• Type: Clock/Calendar/NVSRAM/Y2Kr

Specifications of DS1557WP-120IND

• Memory Size: 4M (512K x 8)
• Time Format: HH:MM:SS (24 hr)
• Date Format: YY-MM-DD-dd
• Interface: Parallel
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 34-PowerCap™ Module
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Figure 3. Clearing IRQ Waveforms
The IRQ/FT pin can also be activated in the battery-backed mode. The IRQ/FT will go low if an alarm
occurs and both ABE and AE are set. The ABE and AE bits are cleared during the power-up transition,
however an alarm generated during power-up will set AF. Therefore, the AF bit can be read after system
power-up to determine if an alarm was generated during the power-up sequence. Figure 4 illustrates
alarm timing during the battery-backup mode and power-up states.
Figure 4. Backup Mode Alarm Waveforms
CE
1
1
=0
8
8
7FFF0h
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