RAM，Maxim Integrated### 非易失 RAM NVRAMNVRAM 是包含 CMOS 静态 RAM 和不可充电锂电池的模块，用于在断开电源时保存数据。 系列中部分器件还集成了实时时钟 RTC。
* Integrated NV SRAM, Real-Time Clock, Crystal, Power-Fail Control Circuit and Lithium Energy Source * Clock Registers are Accessed Identically to the Static RAM. These Registers Reside in the Eight Top RAM Locations * Totally Nonvolatile with Over 10 Years of Operation in the Absence of Power * Access Times of 85ns and 100ns * BCD-Coded Year, Month, Date, Day, Hours, Minutes, and Seconds with Leap Year Compensation Valid Up to 2100 * Power-Fail Write Protection Allows for ±10% VCC Power Supply Tolerance * Lithium Energy Source is Electrically Disconnected to Retain Freshness Until Power is Applied for the First Time * DS1643 Only DIP Module * Standard JEDEC Byte-Wide 8K x 8 RAM Pinout * DS1643P Only PowerCap Module Board * Surface Mountable Package for Direct Connection to PowerCap Containing Battery and Crystal * Replaceable Battery PowerCap * Power-Fail Output * Pin-for-Pin Compatible with Other Densities of DS164XP Timekeeping RAM
