Ramtron International Corporation introduced several new members of its Processor Companion family. The FM3204, FM3216, FM3264, and FM32256 devices combine a nonvolatile ferroelectric random access memory (FRAM) with a processor supervisor and additional peripheral functions. Ramtron's Processor Companion family provides commonly needed system functions for a variety of automotive, consumer, communications, industrial, metering, and computing applications.
The FM32x Processor Companion family includes a choice of 4Kb, 16Kb, 64Kb, or 256Kb of nonvolatile FRAM with a processor supervisor that features a programmable low-VDD reset, a programmable watchdog timer and a manual reset function. Additional peripherals include a nonvolatile event counter, a lockable 64-bit serial number area and a general-purpose comparator that can be used for an early power-fail (NMI) interrupt or other purpose. The FM32x differs in only one way from the previously announced FM31x Processor Companion in that it does not include a real-time clock (RTC).
"We found a number of customers that would like to develop hardware platforms for end markets in which some need timekeeping functions and others do not, but which are otherwise very similar," stated Mike Alwais, vice president, FRAM products, at Ramtron. "For example, an electric meter may require time-of-use-based tariffs in one country but not in another. However, the hardware needed to measure electric power is otherwise the same. Another example is an aftermarket car radio, which will usually have a clock, but some OEM car models have the clock centrally located and displayed on the dashboard rather than on the radio," he said.
Excluding the clock, the FM32x is identical to the FM31x. It offers a common pinout, and even the relevant register locations are identical so that software written for one version will work with the other. Engineers that standardize their designs on the FM31x and FM32x families can design a common PCB and mount the relevant component depending on the end market.
Implementing these complementary but distinct functions using an advanced 0.35-micron manufacturing process allows them to share a common interface and fit in a tiny 14-pin SOIC package, eliminating the need for multiple parts on a system board. An industry-standard 2-wire bus is used to access the memory and control all functions. All devices operate from 2.7 to 5.5V and are available in 4Kb, 16Kb, 64Kb, and 256Kb densities.
Processor Supervisor - provides a host processor with two basic functions: detection of power supply fault conditions and a watchdog timer to escape a software lockup condition. A reset pin (/RST) drives the processor-reset input during power faults, power-up and -down, and software lockups. The reset pin also provides a switch debounce function to facilitate manual reset inputs.
Early Power-Fail Interrupt - an early power-fail warning can be provided to the processor well before VDD drops out of specification. The comparator is used to create a power-fail interrupt (NMI). This is ideal for saving critical data in nonvolatile FRAM.
Serial Number - a separate memory location to write a 64-bit serial number is provided. It is a writeable, nonvolatile memory block that can be locked by the user once the serial number is set. Once locked, the serial number can't be altered.
Event Counter - offers the user two battery-backed event counters, which are 16-bit each, cascading to one 32-bit counter, including a programmable edge detect. This unique counter can be used to log system intrusions (tamper events) or virtually any other general-purpose event.
Backup Power - the event counters are intended to be permanently powered. When the primary system power fails, the voltage on the VDD pin will drop. When VDD is less then 2.5V, the event counters will switch to the backup power supply on VBAK. The backup source can be either a battery or a capacitor.
Trickle Charger - facilitates capacitor backup. The VBAK pin can optionally provide a trickle charge current. Data is nonvolatile, so it won't be lost if the capacitor fails.
Memory - the Processor Companion family is provided with choices of 4Kb, 16Kb, 64Kb, or 256Kb of nonvolatile FRAM memory. FRAM memory technology replaces system SRAM or nonvolatile memory, since it reads and writes at bus speed with no delay and offers unlimited write cycles.
Pricing and Availability
Samples are available for the FM3204, FM3216, FM3264, and FM32256 in a 14-pin SOIC package, with prices starting at $2.04 for 4Kb, $2.34 for 16Kb, $2.71 for 64Kb, and $3.97 for 256Kb for 10,000-piece quantities.
For more information about FRAM products, go to http://www.ramtron.com/doc/Products/processor.asp