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FM21LD16: 2-Mbit (128 K × 16) F-RAM Memory | Cypress Semiconductor

FM21LD16: 2-Mbit (128 K × 16) F-RAM Memory

Last Updated: 
Aug 17, 2015


  • 2-Mbit ferroelectric random access memory (F-RAM) logically organized as 128 K × 16
    • Configurable as 256 K × 8 using UB and LB
    • High-endurance 100 trillion (1014) read/writes
    • 151-year data retention (see the Data Retention and Endurance table)
    • NoDelay™ writes
    • Page mode operation to 30-ns cycle time
    • Advanced high-reliability ferroelectric process
  • SRAM compatible
    • Industry-standard 128 K × 16 SRAM pinout
    • 60-ns access time, 110-ns cycle time
  • Advanced features
    • Software-programmable block write-protect
  • Superior to battery-backed SRAM modules
    • No battery concerns
    • Monolithic reliability
    • True surface mount solution, no rework steps
    • Superior for moisture, shock, and vibration
  • Low power consumption
    • Active current 8 mA (typ)
    • Standby current 90 μA (typ)
  • Low-voltage operation: VDD = 2.7 V to 3.6 V
  • Industrial temperature: –40 °C to +85 °C
  • 48-ball fine-pitch ball grid array (FBGA) package
  • Pin compatible with FM22LD16 (4-Mbit) and FM23MLD16 (8-Mbit)
  • Restriction of hazardous substances (RoHS) compliant

Functional Overview

The FM21LD16 is a 128 K × 16 nonvolatile memory that reads and writes similar to a standard SRAM. A ferroelectric random access memory or F-RAM is nonvolatile, which means that data is retained after power is removed. It provides data retention for over 151 years while eliminating the reliability concerns, functional disadvantages, and system design complexities of battery-backed SRAM (BBSRAM). Fast write timing and high write endurance make the F-RAM superior to other types of memory.

The FM21LD16 operation is similar to that of other RAM devices and therefore, it can be used as a drop-in replacement for a standard SRAM in a system. Read and write cycles may be triggered by CE or simply by changing the address. The F-RAM memory is nonvolatile due to its unique ferroelectric memory process. These features make the FM21LD16 ideal for nonvolatile memory applications requiring frequent or rapid writes.

The FM21LD16 includes a low voltage monitor that blocks access to the memory array when VDD drops below VDD min. The memory is protected against an inadvertent access and data corruption under this condition. The device also features software-controlled write protection. The memory array is divided into 8 uniform blocks, each of which can be individually write protected.

The device is available in a 48-ball FBGA package. Device specifications are guaranteed over the industrial temperature range –40 °C to +85 °C.