DS12C887

• Product Introduction

DS12C887 Overview

DS12C887 real-time clock (RTC) can be used as a drop-in replacement for the DS1287. DS12C887 offers a real-time clock/calendar, timed alarms, three shieldable interrupts (sharing a single interrupt output), programmable square wave outputs, and 113 bytes of RAM. DS12887 integrates crystal and lithium batteries in a 24-pin module DIP package. DS12C887 added century bytes within 32h of the address. For months less than 31 days, the date of all devices can be automatically adjusted at the end of the month, with leap year compensation. DS12C887 configurable in 24-hour or 12-hour format with AM/PM indication. Precise temperature compensation circuitry is used to monitor VCC status. Once the primary power failure is detected, the device can automatically switch to a backup power supply. DS12C887 accessed through a multiplexed, byte-width interface that supports both Intel and Motorola modes.

DS12C887 Characteristics

• 直接替代IBM AT计算机时钟/日历
• RTC计算秒、分、时、星期、日、月、年信息， 具有润年补偿，有效期至2099年
• 用二进制或BCD表示时间
• 具有AM、PM标示的12小时模式或24小时模式
• 夏时制选择
• 可选择Intel或Motorola总线时序
• 接口配合软件可寻址128 RAM
• 14字节时钟与控制寄存器
• 113字节通用、电池备份RAM3
• 三路中断可分别通过软件屏蔽与检测
• 闹钟可设置为每秒一次至每星期一次
• 周期可设置在122μs至500ms
• 时钟终止刷新周期标志
• 可编程的方波输出信号
• 自动电源失效检测和切换电路
• 可选则集成了晶体和电池的DIP模块(EDIP)封装
• 可选的工业级温度范围
• 通过美国保险商实验室协会(UL)认证

DS12C887 Applications

• 嵌入式系统
• 网络集线器、桥接器和路由器
• 安全系统
• 电表