Author Archives: Andi

Where Would You Apply Crowbar Protection?

Crowbar is an appliance typically used by construction workers. It is a heavy steel rod with one of its ends pointed and the other shaped like a spatula – both very useful for digging or breaking up construction rubble. Normally, one would not associate such a crude instrument for use by engineers dealing in electronics, were it not for one unusual property of the crowbar. Throw it across a power line, whether accidentally or with a purpose, and the power line trips – a fail-safe arrangement to protect the load in case of an emergency.

In electronics, a crowbar protection is generally an electronic circuitry placed across the outputs of a power supply. It activates to protect the load against overvoltage. When it activates, it shorts the output terminals – the crowbar action. This serves to blow the fuse, trip the circuit breaker or to shut down some part of the circuit so that power to the load is cut off. Most power supplies, whether low- or high-voltage, employ this kind of protection.

The crowbar protection circuit has a sensor that monitors the output voltage of the supply, comparing it against a preset value. When an overvoltage occurs, it triggers the crowbar circuit, which in turn short circuits the output terminals, thereby cutting off power to the load.

Crowbar devices typically use one of two types of components as their main protection. These are the Silicon Controlled Rectifier or SCR, and the Metal Oxide Semiconductor Field Effect Transistor or MOSFET. The design of the monitoring circuit of the crowbar depends on the sensitivity of the load circuit to be protected. For instance, the reaction time of the monitoring circuit depends on how long the protected circuit can survive the excess voltage without damage, and the response time of the main protection device.

Several fault-conditions may lead to possible over voltages. These include a fault in either the power supply or the load, and operator error. Present day electronics are sensitive and often operate at very low voltages with small margin. That makes it imperative to ensure that the safe voltages are not exceeded, and sensitive and expensive equipment remain undamaged.

Although blowing the fuse is a popular method of protecting a circuit, it has its disadvantages. Recovery is only possible by manually replacing the fuse, once the fault condition is repaired. This is a time consuming affair, and not helpful for low downtime appliances. Therefore, most engineers prefer a fold-back type of crowbar protection.

In a typical crowbar protection, the entire load current is diverted from the load and directed to the short circuit across the output terminals. This is constant current limiting and puts the fuse under tremendous stress, causing it to blow, thereby protecting the power supply and its load. In contrast, with the fold-back crowbar protection, the load current through the short circuit reduces once the crowbar has activated and shorted the outputs.

The short circuit current reduces to the extent that the power dissipated by the supply can remain within its safe operating area. This prevents the fuse from blowing, and at the same time, the power supply keeps the load circuit safe because of the crowbar action. As soon as the cause of the overvoltage is repaired, the power supply resumes automatically.

Driving Motors and Servos with the ZeroPi

If you are looking for a development board for the 3-D printer you are designing, ZeroPi may be the best fit. Suitable for use with the Arduino and the Raspberry Pi (RBPi) single board computers, ZeroPi offers an integrated solution allowing makers to build projects easier and faster.

This miniature board for the Arduino and RBPi is a next generation development kit ideal for maker projects that involve any type of robotic motion control including CNC milling and 3-D printers. According to technical specifications, the ZeroPi runs on an Atmel 32-bit, ARM Cortex M0+ processor the SAMD21J18 operating at 48 MHz. This MCU is fully compatible with the RBPi, the Arduino Zero, and so many more hardware resources that drive robots.

Capabilities of the ZeroPi include driving and controlling 11 micro servos and 8 DC motors simultaneously. Alternatively, you can use ZeroPi to control four stepper motors. The four-channel SLOT module is compatible with the regular DC motor and stepper motor drivers such as the TB6612 DC motor driver and the A4988 or DRV8825 Stepper motor drivers.

According to the team that developed ZeroPi, the board works perfectly for a 3-D printer, acting as its mainboard. Additionally, with the ZeroPi and a web interface, it is possible to control the 3-D printer remotely. The team claims to have successfully ported the Repetier and Marlin firmware to ZeroPi. They have tested the combination on Delta and I3 open source 3-D printers, with success. The combination directly controls the printer without requiring any additional expansion boards. Compared to the Mega2560, ZeroPi is all open-source, cheaper and four times faster. In addition, it is only half the size of the Mega 2560. All board schematics, Repetier and Marlin firmware, and the user manual for the ZeroPi is available on GitHub.

Apart from 3-D printers, you can also use the ZeroPi for driving laser cutters and CNC mills. In fact, it is perfectly possible to use the ZeroPi for developing an all-in-one mainboard suitable for all three. This open-source mainboard can serve the creativity and innovation of an entire community, advancing their ambitions. That makes the ZeroPi useful to several people and projects.

Some key features of the ZeroPi are operating voltage of 3.3 V, 2 UARTs, 35 general-purpose IO pins, 4 analog input pins, 12-bit ADC channels, 1 analog output pin, 10-bit DAC. Other features include external interrupts on any pin except pin 4, 7-mADC current per IO pin, Flash memory of 256 KB, SRAM of 32 KB. The ZeroPi board has dimensions of 73 x 61 mm.

You can program the ZeroPi from the Arduino IDE using example codes available for specific functions such as temperature monitoring and encoder readout. By connecting the ZeroPi to the GPIO connector of the RBPi, it is possible to add further functionality such as controlling the ZeroPi via Bluetooth, wireless control, and tablet. By installing a web interface, it is possible to control the motors and servos remotely. The interface can use Java Script as well.

Does the NexDock Work With The Raspberry Pi 3?

Although smartphones are getting smarter all the time, some of their landmark features limit their use as a laptop, two of them standing out prominently. One is the lack of a full-fledged keyboard and the other, a reasonably sized display screen. Therefore, although the smartphone has nearly the same computing powers as your laptop, it fails to compete successfully with a laptop or netbook.

To remedy the situation, you can take recourse to the lapdock. This is a mobile docking station with a built-in battery, a Bluetooth keyboard, and a 14” LCD monitor. While you can connect your smartphone or tablet to the lapdock, it also allows you to dock your single board computer such as the Raspberry Pi or RBPi with equal ease. The lapdock can make use of any device that has an HDMI output.

NexDock is a budget lapdock with a built-in battery that supplies 3.8 V with a capacity of 10,000 mAH. It provides the user with a Bluetooth keyboard, a 14” display, two USB ports, and one micro SD card slot. NexDock has two small loudspeakers built-in, but you can use headphones on the 3.5 mm socket. This is a revolutionary concept helping to harness the productivity of single board computers, tablets, and smartphones.

Single board computers such as the RBPi3 come with an HDMI output. That makes the RBPi3 a suitable candidate for use with the NexDock. As the NexDock uses the operating system of the RBPi, you can use either Linux or Windows 10 easily. An advantage with using the Windows 10 is its Continuum feature, which allows switching between touch and desktop modes. Using NexDock with the iPhone or Android provides the user with a substantial screen size and upgrades the productivity.

This revolutionary budget concept allows you to have the best of both worlds with an SBC, a smartphone, tablet or mini PC. Simply plug in your device and continue to work with it without fear of the battery running out of juice. The massive battery in the NexDock lasts for days on one charge. That means you now have a powerful laptop to take anywhere and do anything along the way. The device measures 351 x 233 x 20 mm, and weighs 1,490 gm. Most of this weight is due to the generously sized battery with a capacity of 10,000 mAH. The display screen is 14.1 inch TN, with a resolution of 1,366 x 768 pixels.

Although the main functionality of the NexDock is boosting mobile productivity, it can also serve to turn your RBPi into a full-fledged computer. However, you can also use it as a secondary portable monitor, a game controller for your iPhone or use it as a dual-screen for AirPlay-enabled games.

For the future, the company is planning to build high-end mini-computers, where you can swap parts. These will have the capability to connect with devices via a single USB-C port. This will serve to reduce the cost of upgrading your computer, as the process serves to separate components that need frequent updates from those that do not. Therefore, while you retain the keyboard, display and the battery, you can update the processor, memory, and operating system as you wish.

What are Light-Emitting Capacitors good for?

HLEC, or Hyper-elastic Light-Emitting Capacitors are good for making electroluminescent skin for robotics, and you can do a lot with them. That is according to Dr. Rob Shepard of Cornell University and his team of graduate students, who have published a paper on the electroluminescent skin they have developed recently.

The team was inspired to develop the electroluminescent skin by observing several cephalopods such as the Octopus. According to the team, their material can change its color, just as an octopus can, including changing its size to fit into areas that structures that are more rigid cannot. For instance, the skin continues to emit light even when it has been stretched to about six times its original size.

Layers of transparent hydrogel electrodes separated with elastomer sheets as dielectric make up these HLEC or Hyper-elastic Light-Emitting Capacitors. Panels of these capacitors, integrated into robotic systems, and outfitted with sensors act as ideal health-based sensor applications for wearables. The team at Cornell has fabricated one robotic system from three panels and it is capable or crawling. With each panel consisting of six layers, the robot crawls along with worm-like movements, using two pneumatic actuators that alternately inflate and then deflate. You can see the stretchable skin and its crawling action in the video here.

Although the team is in raptures over how well the HLEC panels function, their next step is convert the material into practical devices with applications – find a reason to use it, as they say.

The team expects the development of uses for these new panels to lead to some innovative applications. Although at present, the speculated devices range primarily from health care to industries related to transportation, there is a significant interest in future robotic application as well. The latter is based on the interest in advancing the way robots interact with humans.

For instance, the robot Atlas, from Boston Dynamics, looks formidable enough to crush you were you to give it a hug accidentally. Humans prefer soft and puffy robots, and in the future, robots may even be able to change color based on the mood of the person in front. People generally grow an innate fear of robots after having watched T-800 in movies such as ‘The Terminator’. However, future robots such as Baymax should help make a difference in their thinking. According to Professor Shephard, HLEC panels can be part of the break-through.

It is important to get the human-robot interactions right. Simple things such as the ability to change their color can let robots make emotional connections with humans. This could be in response to the tone of the room or the mood of the humans in it.

This new electroluminescent skin has a huge potential for all kinds of new devices. However, it needs the assistance of other engineers as well to discover new applications and make use of this technology. Primarily, the material scientists who developed this skin are planning to use this for life-saving wearable health monitors. However, it could easily be used as a robot that fits into tight areas. Once the HLEC panels are commercially available, surely, there will be many people to think of additional innovative applications.

Advanced Applications Need Alternate Switch Technologies

Although conventional reed switches have been in use for their excellent properties, their large size makes them difficult to integrate in advanced applications. Most equipment now use miniature components and manufacturers have found a way to reduce the size of reed switches to match. They now use HARM MEMS or High Aspect Ratio Microfabrication MEMS technology to make miniature reed switches, keeping all their desirable properties intact.

Reed switches are popular because they do not require power to operate, they offer milliohms of ON resistance, and tera-ohms of insulation when OFF. They are immune to ESD or electrostatic discharge. Moreover, they require very little additional circuitry to operate and hence, take up very little real estate on the printed circuit board. Some advanced applications where the alternate HARM MEMS reed switches are useful are as follows.

Small Portable Hearing Aids

The baby-boomer market is increasingly in need of small portable medical devices such as hearing aids or hearing assistance devices. HARM MEMS switches are ideal for the control functions in these devices. As the user preference for small, almost unnoticeable hearing aids grows, the ever-shrinking devices are making increasing use of the tiny magnetically operated switches for functions such as Telecoil operation and program switching. As these switches need no power to operate, the once bulky behind-the-ear hearing aids are disappearing into the ear canal itself. Since batteries have also shrunk, the zero power operation of the microfabrication reed switches is a boon for the user.

Endoscopes the Size of Capsules

No one forgets the trauma of getting an endoscope done to know what is wrong within his or her gastrointestinal tract. However, that might soon be outdated, as HARM MEMS can shrink the endoscope down to the size of a capsule, which the patient swallows. As the pill shaped endoscope passes down the gastrointestinal tract, its one or more video cameras capture images lit by its white LED headlamps, also a part of the pill.

As the device is small enough to be swallowed easily, the capsule endoscope has electronic circuitry that is highly miniaturized, so that it can reach where conventional endoscopes or colonoscopes cannot. The tiny pill requires a mechanism to allow it to start functioning just before it is swallowed. In addition, there must be no drain from the tiny batteries when the device is in storage. Active switches are not helpful here, as they draw current even when inactive and hence reduce the shelf life. HARM MEMS switches are the best fit here because of their tiny size and zero power consumption.

Insulin Delivery Pumps

All over the world, diabetes is increasingly affecting people of all ages. In the most severe form of this disease, insulin must be administered multiple times daily to the body. There are two ways to do this – either by multiple daily syringe injections or via insulin pumps. The pumps generally contain a disposable insulin reservoir. The pump unit must reliably detect this reservoir. Modern insulin pumps are small credit card sized and contain a HARM MEMS reed switch, which is activated by a magnet attached to the reservoir.

How Can I Protect My Raspberry Pi?

By connecting the Single Board Computer to the Internet, you actually run the risk of compromising your Raspberry Pi or RBPi to different types of attacks from malicious persons. However, as several advantages of an Internet connection far outweigh such risks from attackers, there is merit in looking for ways to mitigate them. Spain Hardware from Madrid is venturing on a Kick Starter project to enable hardware protection for the RBPi.

When your RBPi requires secure communication, you can rely on the PiSec module, from Spain Hardware, to provide the necessary assistance. PiSec, being a protecting module, uses its own hardware to protect and encrypt all the inputs and outputs on the RBPi. PiSec protects the RBPi from all angles – SD card, USB, and Ethernet, offering a strong hardware base security that includes Elliptic curves and AES-256 XTS.

PiSec, based on a True Random Number Generator, works by generating safe and strong encryption keys and certificates. Internally, PiSec uses a protected file system that it protects with an internal certificate making it impervious to unauthorized access. The processor on board the PiSec module makes use of Elliptic Curve Cryptography to reduce its own overhead and speed up the process of verification.

PiSec provides protection complying with certificates such as the AES 256-bit XTS Military Grade Encryption and X.509. Repeated attempts after a predefined number of unsuccessful attempts to gain access to the RBPi results in the PiSec automatically blocking access. This helps in preventing DoS or Denial-of-Service and brute force attacks.

Typically, you can use your RBPi right out of its box, including its Ethernet connection, the USB ports, and its SD card. You can use the SBC to collect, store, and transfer data, but the RBPi handles all this using clear text, which anyone can intercept and read. You can use your tiny but powerful computer in several ways, for instance, as a standalone PC as a storage system, data logger, and standalone server, a device to control complex systems/machines, or used with licensed software. In all these cases, it will certainly hurt your business if your data is exposed and someone sniffs the actuator or the sensor communication lines and steals your telemetry.

There are several ways to achieve security through software generated keys and certificates. However, relying on a hardware solution is a far better solution, as most of such software solutions do not use a true random generated number. PiSec offers this strong protection security to the entire RBPi, including all devices on its SPI bus, without overloading the processor of the RBPi, nor collapsing its OS. Being a hardware solution, it is simple enough to plug the PiSec on your RBPi, without any necessity of a learning curve or any previous experience on security.

Features of the PiSec include a TRNG or true random number generator. It obtains the random seed from on-board white noise generators that are FIPS and AIS 31 compliant, and with a very high entropy level. TRNG is crucial to creating strong secure keys and certificates.

Integrating Piezoelectric Flexure Actuators

The familiar reed switch comes with a unique set of properties. These include ON resistance of the order of milliohms, OFF resistance of the order of tera-ohms, total immunity to ESD or electrostatic discharge, hot switching capability of about one watt, and almost zero power operation. However, as all electronic components are shrinking to surface mount sizes of 0402, 0201 and even to 01005 (0.4 x 0.2 mm), the large size of the reed switch is anachronistic. Since 70 years of its invention, the conventional reed switch has been steadily shrinking. What began with a 50 mm long glass tube in 1938 has come down to about 5 mm today.

However, even after a sort of following Moore’s law of ever-shrinking transistor size on integrated circuits, reed switches have now reached a brick wall. The fundamental limitations of physics and manufacturing are preventing the conventional reed switches from going below the 5 mm size. Now, a new technology promises to break this barrier of 5 mm size, while retaining all the desirable properties of the reed switch. Manufacturers are using HARM, or High-Aspect Ratio Microfabrication MEMS technology. For instance, reed switches such as the RedRock RS-A-2515 piezoelectric flexure actuators from Coto Technology is based on this technology.

Alternatives to reed switches also exist. For instance, there are Hall Effect switches, AMR or Anisotropic MagnetoResistive switches, and GMR or Giant MagnetoResistive switches in the market. However, all the above are active switches, requiring a power supply to operate them. This is a disadvantage related to these active switches, as they add to circuit complexity and take up PCB real estate. Active switches require three electrical connections instead of two – one for supply power, one for the return ground and the third for the sensor signal.

Active switches have further disadvantages in that they require external circuit elements such as bypass capacitors or pull-up resistors. This increases the cost and effective size of these multi-component switching systems. There is additional complexity as these can only switch milliamp-level currents, and extra buffer circuitry is necessary for switching higher currents. Active switches are also susceptible to damage from ESD. In contrast, reed switches made from the HARM MEMS technology has none of the above disadvantages.

Switches made from the HARM MEMS technology offer very small size, high-current hot-switching capability, and zero-power operation. This performance makes the technology suitable for a wide range of applications including automotive and medical. For instance, HARM MEMS technology allows making endoscopes the size of a pill that patients simply swallow, nearly invisible and tunable hearing aids, convenient insulin delivery systems, and some exciting new automotive switching applications.

Although motor vehicles are large systems with enough battery power, conventional affordable reed switches have been widely used for a variety of functions such as ABS systems, gear lever position sensing, and door lock control. Smaller reed switches are also necessary in vehicles for sensing various fluids, for instance, brake fluids. Usually, a single reed switch, triggered by a float magnet in the fluid reservoir indicates a binary position – there is either enough fluid, or there is none.

Tractor Beams are a Possibility Now

For some time now, science fiction has been predicting the tractor beam, the strange column of energy that can transport everything from living beings to inanimate objects through space. Now this long-envisioned chunk of technology from science fiction is en-route to becoming science fact. At the Public University of Navarre in Spain, scientists are successfully manipulating tiny objects in midair. They are doing this with what they claim are acoustic holograms.

Ordinarily, holograms are three-dimensional optical structures, that is, they are made from light. More specifically, they are made by photons diffracting through interference patterns on a holographic plate. Although not popularly known, sound waves can do this as well. Sound waves, when interfering constructively and destructively with ultrasonic waves, can generate 3-D structures. That allows the sound waves to exert force on objects and behave in the same way a tractor beam does.

For instance, scientists have earlier demonstrated acoustic levitation techniques. These can suspend particles within the standing ultrasonic wave created by a single array aimed at a reflector, or between a pair of ultrasound emitter arrays. By varying the phase of the ultrasound, the nodes can move, thereby transporting the particles along a single axis. However, the acoustic levitation technique is fundamentally limited because the design relies on a fixed enclosure. Acoustic holograms are a step forward since they accomplish the same with only a single acoustic emitter and do not require any special enclosure.

These 3-D structures, made of sound or acoustic holograms, are actually bridging the gap between optical and acoustical trapping – shaped in the form of bottles, twisters, or tweezers. Scientists produce them typically from 400 numbers of 10 mm ultrasonic transducers arranged in an array of 20 x 20. Each transducer generates 40 kHz waves of ultrasonic sound using programmable relative phase modulation.

Within each transducer, there are two elements – one to determine the shape of the ensuing structure, and another, a holographic lens generated when the sound waves emitted phase-coincide at the structure’s nodal point. When the rapidly oscillating sound waves of the transducer array combine with the holographic lens, they are able to suspend small particles of about 3 mm in diameter in midair. In addition, they also grant control over the position and orientation of the particles.

Brüel and Kjær have done further research on the subject of STSF, Spatial Transformation of Sound Fields or acoustic holography. They have combined acoustic holography with transitory calculations. This allows defining any sound field signifier such as particle velocity, sound intensity, or sound pressure as a function of position and time. They have demonstrated through animated maps the control over a specific property change as a function of time.

Scientists at the Public University of Navarre in Spain have published their findings in Nature Communications. They have successfully levitated, rotated, and otherwise manipulated a tiny ball in midair using a grid of Ultrasonic transducers that send out high intensity sound to create a kind of force field around the object. They moved the tiny ball around the grid as though human fingers were doing the work.

Sleep Better with a Raspberry Pi

Sleep is an integral part of our lives, and lack of quality sleep quickly leads to a whole host of issues related to physical, emotional, behavioral, etc. Quality sleep is linked to a good environment that includes proper bedding, clothing, temperature, humidity, and lighting among other things. Although electronics may not be able to help much with the proper choice of bedding and clothing, a cheap but versatile single board computer such as the RBPi or Raspberry Pi is a good contender for controlling temperature, humidity and lighting during sleep hours.

When using the RBPi for controlling the environment of the bedroom, it is necessary to build an RBPi-based temperature-monitoring network in the house. This helps to get some hard data on the existing temperature trends at different places, so it will be easy to know whether the solutions tried did actually work. Since temperature is to be monitored at different places at the same time, it is necessary to use remote sensors.

You can use temperature sensors such as the single-wire DS18B20 thermometers for inexpensive and accurate temperature measurement. This model has two types of sensors – transistor-sized and waterproof, and you can use either for the purpose. However, people have found the waterproof sensors were easier to position and calibrate, and they were slightly more accurate as well.

Testing the sensors on the RBPi is simple as this SBC supports the DS18B20 sensors by the built-in w1-gpio library. The RBPi allows easy readouts of the 1-Wire devices. You can wire up a few DS18B20s to multiple RBPI, Model A+ and position them at all main parts of the house. It also helps to integrate data from your Nest Thermostat API, if you are using this and collect the local outdoor temperature data as well – use the Weather Underground, for instance. Monitor the temperatures from the different sensors on a rolling 24-hour graph, and you can make out if there is a trend.

It is possible to even out temperature variations in the house by sealing vents and leakages in areas where the temperature dips. However, this may not be enough to raise the temperature to comfortable levels at locations distant from central heating ducts. Moreover, not all walls of the house may receive equal amounts of sunlight, and this may be another reason for the temperature dropping in certain rooms after sunset.

You can use unobtrusive wall-mounted space heaters to boost the temperature up in these areas. Usually, these are slabs of stone with heating wires running through them. Stone has high thermal capacity, meaning it retains and radiates heat for a long time. This arrangement is also safe for use in children’s bedrooms. When used on a thermostat-triggered outlet, the heater only turns on at a select temperature that you choose. You can fine-tune the settings after monitoring the temperature data for a couple of nights.

This project is useful if you are planning to have an extended network, with remote-controlled HVAC using branch air ducts. Individual controls on the branch ducts can control the airflow, so the system efficiency goes up, such as by turning down the airflow to sections of the house where there is no one present.

PINE64 : A 64-bit Contender for the Raspberry Pi

Earlier, a DIY computing project could cost an enthusiast hundreds of dollars. Now, with single board computers such as the Raspberry Pi or RBPi or its latest kin, the Raspberry Pi Zero, anyone can start a new project at the cost of a cup of coffee. Seen from the other side of the fence, a competitor has to include a better choice of components, offer a better price or both. PINE64 Inc. has taken the third route.
PINE54 Inc. is attempting to improve on the legacy so far built up by the RBPi. According to the team, two mathematical constants make up the name of their board – Pi and Euler’s Number e. As it has a 64-bit processor, the name also includes the number 64 along with an A to differentiate it from future versions. The PINE A64 runs on an ARMv8 processor, the Cortex-A53, and is available for just $15.
PINE A64 measures 12.7×7.94cms and uses a 64-bit processor, a quad-core ARM Cortex A53 running at 1.2GHz. A dual-core Mali 400 MP2 handles the graphics. Memory includes a micro SD slot to handle cards up to 256GB and 2GB DDR3 SDRAM onboard. Ports available on the PINE A64 include one gigabit Ethernet, two USB 2.0, one HDMI 1.4 connector for 4K output, a stereo mini-jack connector and a charging circuit for a 3.7V Lithium battery.
PINE64 Inc. will also be offering separate modules to augment the functionality of PINE A64. The modules will add a touch panel port, a 5MP camera port, Bluetooth 4.0 and Wi-Fi connectivity and a 4-Lane MIPI video port. The board runs on 5V power via its micro USB connector, but can fall back on its internal battery with on-board power management.
According to Johnson Jeng, the co-founder of PINE64 Inc., the company has designed a simple, smart and affordable computer. People can use this to bring their next big ideas to life. The 64-bit quad-core single board computer is available at an exceptional price. It is compatible with several open-source platforms, enabling people to build a community of innovation and creativity.
Just like other ARM-based single board computers, you can set up PINE A64 to operate as a gaming console or a mini-computer. You can control your connected home or allow it run your own media center. PINE A64 can operate with Android 5.1, openHAB, Ubuntu Linux, OpenWRT and Kodi. Additionally, it supports Miracast and offers the H.265 video standard to give your 4Kx2K output.
The Raspberry Pi Foundation concentrates on delivering performance without increase in costs, and hence, prefers to retain the ARMv7 architecture for the RBPi family even when ARMv8 64-bit chips are readily available. According to Eben Upton, the founder of the RBPi series, a more powerful processor will certainly come with a boost in the prices.
With companies now launching new Systems-on-a-Chip or SoC platforms that are 64-bit and super-cheap, PINE64 Inc. has decidedly stolen a march over the RBPi series. Allwinner started this trend with the 64-bit Cortex A53 processor for their tablets and now PINE64 Inc. has used it to power their PINE A64, A64+ and A64+ 2GB boards.