DS1556 Overview
A0 A16 - Address Input DQ0 DQ7 IRQ/FT RST CE OE WE - Data Input/Outputs - Interrupt, Frequency Test Output (Open Drain) - Power-On Reset Output (Open Drain) - Chip Enable - Output Enable - Write Enable VCC - Power Supply Input GND - Ground N.C. DS9034-PCX+ or DS9034I-PCX+ required (must be ordered separately). A “+” in top mark denotes a lead(Pb).
DS1556 Key Features
- Integrated NV SRAM, Real-Time Clock (RTC), Crystal, Power-Fail Control Circuit, and Lithium Energy Source
- Clock Registers are Accessed Identically to the Static RAM; These Registers Reside in the 16 Top RAM Locations
- Century Byte Register (i.e., Y2K pliant)
- Totally Nonvolatile with Over 10 Years of Operation in the Absence of Power
- Precision Power-On Reset
- Programmable Watchdog Timer and RTC Alarm
- BCD-Coded Year, Month, Date, Day, Hours, Minutes, and seconds with Automatic LeapYear pensation Valid Up to the Year 210
- Battery Voltage-Level Indicator Flag
- 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