L20G20IS Gyroscope: The secret behind the perfect picture

STMelectronics introduces a super tiny two-axis gyroscope (L20G20IS), a Micro-Electro-Mechanical system (MEMS) designed for the optical image stabilization for Smartphones with less energy consumption compared to its predecessor (L2G2IS).

A gyroscope, or gyro for short, adds an additional dimension to the information supplied from the accelerometer by tracking rotation or twist. An accelerometer measures linear acceleration of movement, while a gyro on the other hand measures the angular rotational velocity.

The gyro and the accelerometer work together to detect the rotation of phone and other features like tilting of phone while playing racing games, enhancing the overall gaming experience or in this case, achieving optical image stabilization.

The L20G20IS ultra-compact square gyro uses 25% less surface to shrink camera module size, simplify circuit design and allowing development of thinner devices. The gyro fixes the thin substrates deformations resulted by smartphone moves to ensure consistent measurements for image stabilization.

Features:

  • ±100 dps / ±200 dps full-scale range
  • 5 degree phase delay · 3.8 mdps/√(Hz) rate noise density
  • Wide supply voltage range: 1.7 V to 3.6 V
  • Low-voltage compatible IOs
  • 3- and 4-wire SPI digital interface
  • Embedded temperature sensor
  • Embedded self-test
  • Integrated low-pass filters with user-selectable bandwidth
  • Power-down and sleep modes for smart power saving
  • ECOPACK®, RoHS and “Green” compliant
  • Volume (2.0 x 2.0 x 0.7)mm
  • Zero-rate Level: 0.03dps/°C (range: -20°C to 75°C)

Also L20G20IS includes a sensing element and an IC interface capable of providing the measured angular rate to the application through an SPI digital interface. It is compatible with single- or dual-camera modules and is available now in the 12-lead 2mm x 2mm LGA package.

Zero-rate level: This value indicates “the deviation of an actual output signal from the ideal output signal if no acceleration is present”, or more clearly the output value that will be generated when there is no movement on the device. This is very important for the phone, it needs to know when it is not moving to be able to stabilize the images with the appropriate values.

Results

Smaller but more efficient gyroscope! The L20G20IS boots 30% faster (in less than 70ms) consuming just 1.4mA (50% less of current than usually). Although, the temperature can affect the sensitivity and the zero-rate level of the gyro, producing wrong measurements for image stabilization by the phone. However, the L20G20IS device has a integrated temperature sensor to guarantee sharper images to the users even with long exposure times.

The smart-camera software saves even more battery with the power-down and sleep modes. Another improve is the  suppression ratio of 6dB, it gives outstanding optical correction to banish camera shake from smartphone photography.

Source:  Micro-Electro-Mechanical Systems (MEMS). ST is a world leader in MEMS devices for mobile applications, with more than 900 MEMS-related patents and patent applications worldwide.

Brand New BiCMOS Flexible Transistor

 

The transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things since its very first practically implemented device as a point-contact-transistor invented in 1947 and getting the Nobel Prize in Physics in 1956.

Now, engineers from the University of Wisconsin-Madison (UW-Madison) have built the most flexible, fully-functional transistor in the world!  The BiCMOS  (Bipolar Complementary Metal Oxide Semiconductor) thin-film transistor has all current transistor’s characteristics: speed, carrying large current and low dissipation – but it is extremely flexible.

This is an interesting advance that could open the door to an increasingly interconnected world, enabling manufacturers to add smart wireless capabilities to any number of large or small products that curve, bend, stretch and move.

Making traditional BiCMOS flexible electronics was difficult, in part because the process takes several months and requires a multitude of delicate, high-temperature steps. Even a minor variation in temperature at any point could ruin all of the previous steps. This fabrication process is not currently as commercially viable for most of applications.

However, the engineers fabricated their flexible electronics on a single-crystal silicon nanomembrane on a single bendable piece of plastic. The secret to their success is their unique process, which eliminates many steps and slashes both the time and cost of fabricating the transistors.

This new electronic has the potential to change the electronic’s industry in a new way. Everything touched by electronics (computers, microcontrollers, sensors…) could be completely flexible due the easily of this new technology to scale up to commercial levels.

The vast majority of transistors are now produced in integrated circuits. A logic gate consists of up to about twenty transistors whereas an advanced microprocessor, as of 2009 and with a cost of just a couple of usd, can use as many as 3 billion transistors. This is the best transistor’s advantage: mass-production with a extremely low cost.

For that reason, the transistor is the key active component in practically all modern electronics. The transistor is on the list of IEEE milestones and many consider it to be one of the greatest inventions of the 20th century.

This new flexible transistor could be in future electronic boards for a flexible electronics development and applications never even seen before. Definitely, the future is now.

The “Neuropixels” probe records brain signals

 

After $5.5 millions collaboration and a lot of work during the past four years of engineers at Imec, the next-generation electrodes called Neuropixels probe were designed to record hundreds of neurons in the brain. Imec is an international nano electronics research center dedicated to build and test powerful new devices for detecting neural activity within the brain.

To understand how the brain operates, we must measure the joint activity of a myriad individual neurons distributed across brain regions. Until recently, this has been impossible.

Their success is due to three innovations:

  1. a multiplayer fabrication process that allows 384 interconnects on a thin shank;
  2. on-shank CMOS circuitry that allows 384 sites to be rapidly selected from a total of 966;
  3. on-device processing that amplifies, digitizes, and multiplexes the signals.

Neuropixels thus constitute a self-contained recording system: the data that emerge are already digital, and can be read by a simple, inexpensive interface to a standard computer.

Probe Options

There are four probe options, all four have the same on-probe amplification and digitization, and can all be used interchangeably with the same headstages and recording equipment.

  • Option1 probes (no switches, no amps) have 5mm-long shanks, and have no switches (they can only record from the most distal 384 sites) or on-site buffer amplifiers.
  • Option2 probes (no switches, yes amps) have 5mm-long shanks, and have no switches
  • Option3 probes (yes switches, no amps) have 10mm-long shanks with 960 total sites accessible via switches; they do not have on-site buffer amplifiers.
  • Option4 probes (yes switches, yes amps) have 10mm-long shanks with 966 total sites accessible via switches; they have on-site buffer amplifiers. Option4 probes can only record 276 channels at a time.

In practical terms, the probes with buffer amps (2 & 4) have slightly higher RMS noise levels in saline (~10-12µV RMS compared to 6-9) but may have superior rejection of certain types of noise.

Switched probes (3 & 4) do not seem to have any deficits relative to the un-switched, unless the shorter shank of the unswitched probes is more suitable for your experimental situation.

Basic Probe Details

  • Neuropixels probes have 384 recording channels (i.e. can record 384 signals simultaneously), and up to 966 recording sites (depending on the option)
  • Recording sites are laid out in a checkerboard pattern, see geometry note below.
  • 10 sites per group of 384 are reserved for selection as internal reference sites and cannot be used for recording (whether they are used for referencing or not)
  • Recording sites have ~200k-ohm impedances
  • Shanks are 70µm wide and 20µm thick (for Option1, shank is 50µm wide)
  • Probe weighs 0.3g, headstage weighs 1.1g.

Neuropixels probes represent a significant advance in measurement technology and will allow for the most precise understanding yet of how large networks of nerve cells coordinate to give rise to behavior and cognition.

Preliminary data examples and a user guide are available.