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| Rugged automotive memory technology |
| Ramtron automotive nonvolatile memory is ideal for the new wave of cars that feature improved safety, fuel-efficiency, and enhanced driver experience. Our automotive F-RAM memory products are used by leading auto suppliers in sub-assemblies like smart airbags, stability control, park assist, power train, cockpit instrumentation, and audio entertainment applications. Our Grade 1 (-40°C to +125°C) AEC-Q100 qualified F-RAM memory is built to take the brutal temperatures under the hood of today's sophisticated cars and trucks. Fast write capability, high endurance, low power consumption, and our enduring commitment to zero defects make Ramtron F-RAM technology perfect for your next automotive big-idea. |
- EDR - |
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| An Event Data Recorder, or EDR, is a device installed in some cars and trucks that records vehicle crash or event information. Data stored in an EDR can be analyzed to help determine what the vehicle’s use conditions were before, during and after the crash or event. |
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| Many EDRs continuously record data, overwriting the previous few minutes/seconds until a crash or event occurs. The event,, such as sudden changes in velocity, prevents further overwriting of the data ensuring that the data is available even if the event itself damages the ability of the EDR to record data. |
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| Limitations of EEPROM |
| The wide range of data elements that can be recorded by an EDR include braking status, the speed at impact, steering angle, and whether seat belts were in use. Historically, EDRs have stored information on an EEPROM until recovered from the module. |
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| As the need for higher sampling speeds and more reliable data increase, it becomes less desirable to use EEPROM as the data collection memory. High-speed nonvolatile data writes and virtually unlimited endurance in a monolithic form factor are the key features of F-RAM memory that make it an ideal choice for new EDRs. |
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| The power consumed writing 64Kbits of data to an EEPROM is about 60x higher than that of an F-RAM. The EDR must write data after the event as it has insufficient endurance to be written continuously. However, the event itself could destroy the power supply making this higher power consumption of EEPROM occur at the least desirable time. |
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| Why use F-RAM? |
| Since event data must be written during an accident, designers must be aware that the main power supply could fail. F-RAM is ideal for EDR applications for the following reasons: |
- Audio Systems - |
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- High endurance
Event data — written to F-RAM prior to and during a crash — is not lost if the main power supply fails. F-RAM's high endurance ensures data integrity.
- Fast writes, low power consumption
F-RAM can be written 1000x faster and a billion times more often than EEPROM, at a fraction of the power, so F-RAM-based EDRs can store data at higher intervals over the life of the EDR.
- No delays
Some event data need to be taken as often as every 1-millisecond to properly record the events. Event data generated during a lateral side crash or 'curb trip' roll over need to be taken as often as every 1-millisecond. The slow, 10-millisecond write time and page buffer delay of an EEPROM makes it unsuitable for this purpose. |
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| A number of new car radio formats are emerging on the market. These new formats include Digital Multimedia Broadcasting (DMB) suitable for radio, TV, and datacasting; satellite radio, Digital Audio Broadcasting (DAB), also called Eureka 147 DAB Standard in Canada, Europe, and Asia. |
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| These new formats transmit specialized data alongside the audio. The data may include artist title, music genre, traffic information and weather. |
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| Why use F-RAM? |
| F-RAM is ideal for storing new broadcast format data because the data changes frequently and must always be available immediately after power on. F-RAM enables function-rich audio features. Here are some common examples: |
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- Favorite artist/song alerts
This alerts drivers when their favorite artist or song is being played on any station.
- Favorite station memory
This sorts the thousands of available stations by personal taste using the station's call sign or slogan, name or type. It can also move a channel to a different position or rename it for easy reading.
- Last channel memory recall
This eases accessing the previous program.
- Traffic information collection/storage
Traffic data is downloaded while the vehicle is off and displayed to drivers when they start the vehicle to help them plan their routes. F-RAM's low-power and high endurance makes this feature possible. | |
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| Ramtron's F-RAM has been designed into a variety of auto entertainment systems from high-end after-market systems to OEM equipment. F-RAM stores critical system information without the need for design work-arounds to safeguard against data loss during power down events. |
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| F-RAM may also be used to store the audio parameters associated with the improved sound quality offered by these new radio formats: |
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- Manual adjustment of all the DSP and EQ settings, individual time delay adjustments for each of the channels, and advanced controls for crossover and filter settings on each channel.
- Filter configuration and factory settings including vocal, natural, super bass and flat among others.
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- Smart Airbags - |
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| Early generation airbags deploy in a uniform manner, regardless of accident severity. Today, automotive airbag technology is becoming increasingly smarter, which allows the airbag deployment force to be determined by accident event parameters such as the severity of the crash, the weight of the occupant, and the interaction with other safety systems within a vehicle. Vehicles are also being increasingly fitted with associated event data recorders (EDRs) that collect crash information. The EDR function is normally included in the airbag electronic control unit (ECU). |
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| Sensors throughout the vehicle’s interior send parametric data to the ECU so that the airbag can deploy "intelligently". As more and more sensors are added to cars, more data needs to be collected. F-RAM collects this data at higher frequencies than other memory technologies, enabling the system to act on the timeliest information available. |
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| F-RAM instead of EEPROM/Flash |
| F-RAM is increasingly replacing floating gate technologies such as EEPROM and Flash in automotive safety applications due to the restrictive nature of these technologies. The programming process for EEPROM/Flash takes several milliseconds, too long for safety-critical applications. The programming process is also destructive to the insulating layer of a floating gate memory device, creating limited write endurance of typically 100K to 1000K writes. In automotive safety systems, data are frequently updated. If the requirement is to write the data once per second, a floating gate device would wear out in less then twelve days of operation, whereas F-RAM would have an operating life of more then 31,000 years! |
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| F-RAM possesses a unique combination of key features for smart airbag systems compared with other memory technologies: |
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- Non-volatility
A crash often results in a power outage, so at some point during the event, the ECU loses its connection to the battery. F-RAM memory needs no periodic refresh and when power fails, it retains its data without a battery.
| - Popular Products - |
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| Part |
Description |
| FM24CL16 |
16Kb Serial I2C 3V F-RAM Memory (AEC-Q100 Grade 3) |
| FM25040A-GA |
4Kbit Serial SPI 5V F-RAM Memory (AEC-Q100 Grade 1) |
| FM25640 |
64Kbit Serial SPI 5V F-RAM Memory (AEC-Q100 Grade 3) |
| FM25640-GA |
64Kbit Serial SPI 5V F-RAM Memory (AEC-Q100 Grade 1) |
| FM25C160 |
16Kbit Serial SPI 5V F-RAM Memory (AEC-Q100 Grade 3) |
| FM25C160-GA |
16Kbit Serial SPI 5V F-RAM Memory (AEC-Q100 Grade 1) |
| FM25CL64-GA |
64Kbit Serial SPI 3V F-RAM Memory (AEC-Q100 Grade 1) |
| FM25L04-GA |
4Kbit Serial SPI 3V F-RAM Memory (AEC-Q100 Grade 1) | | |
