MEMS rate sensor features high reliability for accurate dead-reckoning
November 25, 2010 // Christoph Hammerschmidt
With its MEV-50C-R MEMS rate sensor, Murata aims at automotive navigation markets: The device supports dead-reckoning for car navigation devices plus the high reliability and thermal stability required for automotive environments. The rate sensor nevertheless can be used in other applications as well, such as GPS modules or satellite antennas or even sophisticated toys ó radio control helicopter, for example.
The sensor features the second-generation of Murata's technology - the first generation was used in the company's famous bicycle-riding robot, (Murata Boy), and the unicycle-riding robot (Murata Girl).
According to the vendor, the sensor's high temperature stability does away with the need to adjust for temperature drift in software. Temperature drift across the entire operating range, -40 to 85 °C, is just 0.6 degree/s. Materials used in the construction of the rate sensor help to ensure the stable temperature performance of the device. Single-crystal silicon is used for the core MEMS vibrator, while the MEMS element is composed of silicon and pyrex glass, which have very similar temperature expansion coefficients, increasing stability.
Another key factor for rate sensors used in car navigation systems is the start-up drift. It typically takes several minutes after the system is switched on for a GPS signal to be acquired, so dead-reckoning is commonly used during this time. The MEV-50C-R exhibits a low start-up drift of 0.1 degree/s between 0.5s and 5 minutes after start-up. Other features are high linearity of 0.5 percent across the operating range of angular velocity, as well as low cross-axis sensitivity (±5 percent).
The MEMS element uses anodic bonding creating a seal which achieves much better performance than the current industry standard of 10-9 Pa m3/s. The seal did not change its efficiency during air tank/heat shock tests with 2000 cycles of -55 to +125°C (30 min/30 min). This high level of seal allows Murata's MEMS technology to be applied under harsh conditions such as automotive.
The MEV-50C-R measures 10.0- x 6.2- x 2.9-mm and weighs just 0.3 g (maximum). Maximum angular velocity is ±70degree/s. The sensor's unique 'ladder' structure means the part is not influenced by external physical noise (shock or vibration), and thus exhibits more accurate angular-rate information than competing parts.
Saltwater-powered lamp lights up areas with no electricity
July 29, 2015
An LED lamp powered by salt and tap water is being offered as a safer and more efficient means of lighting in areas with ...
Audi to demo OLED exterior lighting at IAA
First color-tunable graphene-based LED is demonstrated
Mobile security report shows malware impacting Android market
Qualcomm enables wireless charging for mobile devices with metal cases
Intel, Micron launch "bulk-switching" ReRAM
July 28, 2015
Intel Corp. and Micron Technology Inc. have launched a new class of non-volatile memory that they have called 3D Xpoint and ...
Demand for radar systems boosts Infineonís chip production
'Test city' opens for autonomous cars
AMS buys environmental sensor business from NXP
- Dual Phase Buck Controller Drives High Density 1.2V/60A Supply with Submilliohm DCR Sensing
- Test environment for the positioning elements of wearable devices
- Automotive Circuit Protection using Littelfuse Automotive TVS Diodes
- Top 5 Challenges for testing Today's Consumer Electronics
InterviewGlobalfoundries' CEO on why FD-SOI and why now
With its latest news Globalfoundries Inc. has not only confirmed itself as a supporter of the fully-depleted silicon-on-insulator (FD-SOI) approach to IC manufacturing but that it also thinks sufficiently ...
Filter WizardCheck out the Filter Wizard Series of articles by Filter Guru Kendall Castor-Perry which provide invaluable practical Analog Design guidelines.
Linear video channel
READER OFFERRead more
This month, Novelda is giving away two full XeThru Inspiration kits worth 1499 US Dollars each, for EETimes Europe's readers to experiment first hand with its XeThru technology.Based on the use of radio waves, rather than infrared, ultrasound or light, the company's X2M1000 Inspiration modules can detect presence just from the chest movement while breathing, and measure both the rate and... MORE INFO AND LAST MONTH' WINNERS...
December 15, 2011 | Texas instruments | 222901974
Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.