Analog Devices DS1557P-70+ 实时时钟 4Meg，非易失性，符合Y2K标准的时间保持器

Function: Alarm, Calendar, Clock, NV Timekeeping RAM, Watchdog Timekeeper

Date Format: YY-MM-DD-dd

Time Format: HH:MM:SS (24 hr)

Mounting Style: SMD/SMT

RTC Memory Size: 512 kB

RTC Bus Interface: Parallel

Moisture Sensitive: Yes

Supply Voltage - Max: 5.5 V

Supply Voltage - Min: 4.5 V

Battery Backup Switching: Backup Switching

Operating Supply Current: 45 mA

Maximum Operating Temperature: + 70 C

Minimum Operating Temperature: 0 C