FM33256B
3V Integrated Processor Companion with F-RAM
Features
Processor Companion
High Integration Device Replaces Multiple Parts
Active-low Reset Output for VDD and Watchdog
Programmable Low-VDD Reset Thresholds
Manual Reset Filtered and Debounced
Programmable Watchdog Window Timer
Nonvolatile Event Counter Tracks System
Intrusions or other Events
Serial Nonvolatile Memory
Real-time Clock (RTC) with Alarm
Low VDD Detection Drives Reset
Watchdog Window Timer
Early Power-Fail Warning/NMI
16-bit Nonvolatile Event Counter
Serial Number with Write-lock for Security
Comparator for Power-Fail Interrupt or Other Use
64-bit Programmable Serial Number with Lock
Ferroelectric Nonvolatile RAM
Fast SPI Interface
256Kb F-RAM
Up to 16 MHz Maximum Bus Frequency
RTC, Supervisor Controlled via SPI Interface
SPI Mode 0 & 3 (CPOL, CPHA=0,0 & 1,1)
High Endurance 100 Trillion (1014) Read/Writes
38 year Data Retention (+75C)
NoDelay™ Writes
Easy to Use Configuration
Operates from 2.7 to 3.6V
Small Footprint “Green” 14-pin SOIC (-G)
Low Operating Current
-40C to +85C Operation
Underwriters Laboratory (UL) Recognized
Real-time Clock/Calendar
Backup Current at 2V, 1.15 A (max.) at +25C
Seconds through Centuries in BCD format
Tracks Leap Years through 2099
Uses Standard 32.768 kHz Crystal
Software Calibration
Supports Battery or Capacitor Backup
The processor companion includes commonly needed
CPU support functions. Supervisory functions
include a reset output signal controlled by either a
low VDD condition or a watchdog timeout. /RST goes
active when VDD drops below a programmable
threshold and remains active for 100 ms (max.) after
VDD rises above the trip point. A programmable
watchdog timer runs from 60 ms to 1.8 seconds. The
timer may also be programmed for a delayed start,
which functions as a window timer. The watchdog
timer is optional, but if enabled it will assert the reset
signal for 100 ms if not restarted by the host within
the time window. A flag-bit indicates the source of
the reset.
Description
The FM33256B device integrates F-RAM memory
with the most commonly needed functions for
processor-based systems. Major features include
nonvolatile memory, real-time clock, low-VDD reset,
watchdog timer, nonvolatile event counter, lockable
64-bit serial number area, and general purpose
comparator that can be used for a power-fail (NMI)
interrupt or other purpose. The device operate from
2.7 to 3.6V.
The FM33256B provides 256Kb memory capacity of
nonvolatile F-RAM. Fast write speed and unlimited
endurance allow the memory to serve as extra RAM
or conventional nonvolatile storage. This memory is
truly nonvolatile rather than battery backed.
A comparator on PFI compares an external input pin
to the onboard 1.5V reference. This is useful for
generating a power-fail interrupt (NMI) but can be
used for any purpose. The family also includes a
programmable 64-bit serial number that can be
locked making it unalterable. Additionally it offers an
event counter that tracks the number of rising or
falling edges detected on a dedicated input pin. The
counter can be programmed to be non-volatile under
VDD power or battery-backed using only VBAK. If
VBAK is connected to a battery or capacitor, then
The real-time clock (RTC) provides time and date
information in BCD format. It can be permanently
powered from external backup voltage source, either
a battery or a capacitor. The timekeeper uses a
common external 32.768 kHz crystal and provides a
calibration mode that allows software adjustment of
timekeeping accuracy.
events will be counted even in the absence of VDD
.
This product conforms to specifications per the terms of the Ramtron standard warranty. The product has completed Ramtron’s
internal qualification testing and has reached production status.
Cypress Semiconductor Corporation
Document Number: 001-86213 Rev. **
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised February 25, 2013
5秒后页面跳转
英伟达新AI芯片Rubin或提前半年亮相
苹果iPhone 17将全系采用三星/LG显示LTPO OLED面板
三星深化印度制造布局，供应链本地化进程加速
芯擎科技“星辰一号”自动驾驶芯片点亮成功，2025年量产在即
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
数据手册
如果您发现信息不准确，
