FM3808

Preliminary FM3808 256Kb Bytewide FRAM w/ Real-Time Clock Features 256K bit Ferroelectric Nonvolatile RAM Organized as 32,752 x 8 bits High Endurance 100 Billion (1011) Read/Writes 10 year Data Retention NoDelay™ Writes 70 ns Access Time/ 130 ns Cycle Time Built-in Low VDD Protection Real-Time Clock/Calendar Function Clock Registers in Top 16 bytes of Address Space Backup Power from External Capacitor or Battery Tracks Seconds through Centuries in BCD Format Tracks Leap Years through 2099 Runs from a 32.768 kHz Timekeeping Crystal System Supervisor Function Programmable Clock/Calendar Alarm Programmable Watchdog Timer Power Supply Monitor Interrupt Output - Programmable active high/low Control Settings Inherently Nonvolatile Generates either Processor Reset or Interrupt Low Power Operation 5V Operation for Memory and Clock Interface Backup Voltage as low as 2.5V 25 mA IDD Active Current 1 µA IBAK Clock Backup Current Description The FM3808 combines a 256Kb FRAM array with a real-time clock and a system supervisor function. An external 32.768 kHz crystal drives the timekeeping function. It maintains time and date settings in the absence of system power through the user’s choice of backup power source – either a capacitor or a battery. In either case data in the memory array does not depend on the backup source, it remains nonvolatile in FRAM. In addition to timekeeping, the FM3808 includes a system supervisor to manage low VDD power ...