Funding for this project was canceled by the project creator on September 12, 2014.
About this project
The Exigo is designed from the ground up to be the absolute best charger available. The highest quality, most advanced technologies, unrivaled performance and robust design leaves nothing on the table. Boasting 3.0A on all 4 ports for 66W of total capacity - the Exigo surpasses all other chargers - even the one that came with your device.
During our own testing, we've seen that the quality of the cable is also important. Low quality, thin wire (usually 28 gauge or smaller) cables result in big voltage drops. Longer cables also mean higher resistance and more severe losses. The hungrier the device attached - the more dramatic the problem. The Exigo compensates for these losses as much as possible, but a high quality, short charging cable helps even more. Our charger cables are low resistance (24 gauge) wire for maximum performance. They're available in your choice of micro-USB, Apple compatible 30-pin or Lightning connectors.
The standard Exigo will come in 4 choices of anodized colors: clear, black, blue and red. If we exceed our funding goal we hope to add several more colors and will ask for your help in choosing them. Customized versions with text and/or images will be laser etched after anodizing according to your specifications (top surface only). All Exigo chargers also include a 24V power adapter and country-specific household power cable.
Special Edition Exigo
The special edition Exigo will be nickel plated for a tough, durable satin finish. Before plating a custom image of your choice will be machined into the top surface (0.03" minimum radius) 0.010" deep to provide a subtly stepped surface. The final product will be a one-of-a-kind, beautiful personalized charger. All Exigo chargers also include a 24V power adapter and country-specific household power cable.
- High precision +/- 10mV RMS output
- 3000 mA current capacity (all 4 ports simultaneously)
- <0.1uV/sqrt(Hz) output regulator spectral noise spec (no load)
- Independent 12-bit, 500kHz ADC final stage voltage trim on all 4 ports
- 70MHz digital signal controller
- Independent current monitoring and limiting on all 4 ports
- All major charging device protocols automatically supported
The Exigo contains power delivery technology unlike any other charger. We’ve taken a page from the ultra-demanding requirements of modern aviation and medical reliability as well as high current demands from Intel i7 motherboards and integrated that multi-phase power technology into our charger. That means patent pending high current capability, low electrical noise and robust components designed to handle dozens of amps of current. On top of that we added dedicated 3.0A microprocessor-controlled voltage regulators on every port. They provide active current and voltage monitoring, charge status analysis, over-current protection and extremely low noise output for every connected device.
Automatic Negotiation of Device Charge Protocol
The Exigo USB charger integrates dedicated intelligence to identify and provide native charger handshakes for all connection profiles encompassing 7 different families of devices.
- Apple (2.5W) : D+ 2.0V / D- 2.0V (earliest iPods - 4th gen and older)
- Apple (5.0W) : D+ 2.0V / D- 2.8V (all iPhones & iPods, iPad Mini, etc.)
- Apple (10W) : D+ 2.8V / D- 2.0V (iPad 1, 2 & 3, iPad mini w/Retina, etc.)
- Apple (12.5W) : D+ 2.8V / D- 2.8V (iPad Air, iPad 4, etc.)
- Samsung (10W) : D+ 1.2V / D- 1.2V
- USB Charging Spec 2007 (7.5W) : D+ & D- shorted together
- Chinese Telecom Standard YD/T 1591-2009 : D+ & D- shorted together
Why does that matter?
When USB was first widely adopted by the market after the introduction of the USB 1.1 standard in 1998, the original specification for power only provided 150mA (0.75W). As time went on, additional specifications for 500mA (2.5W), 900mA (4.5W) and eventually 2A (10W) were established to supply bigger devices. If a device draws too much current the results could be as simple as the charger shutting down, or as disastrous as the charger overheating and self destructing. Because the same connector (USB) is used for all devices, there needed to be a way to indicate to the connected device whether or not it can safely draw higher current. That critical "high power OK" signal is provided through the data lines of the USB cable.
Unfortunately the need for higher power evolved quicker than the standards, so manufacturers developed different techniques to communicate the capacity of the charger to the device and they're neither compatible with each other nor with the current USB power and charging specifications. This is the fragmented situation we're in now - if you want to charge at the maximum rate a device supports you need an Apple-compatible charger to power an Apple device, or a Samsung-compatible charger for a Samsung device, etc. Most chargers either support one proprietary standard or one common standard and nothing else. So even if you do have a high-power charger, it probably only works best with one breed of devices. Many manufacturers side-step this issue by simply calling them "Universal," but all that really means is it will charge anything at the lowest rate the device perceives as safe (usually 2.5W). A tablet that's capable of recharging a dead battery at 12.5W in an hour could actually take 5 hours if it doesn't recognize it's connected to compatible charger. The Exigo solves that issue with dedicated circuitry actively sensing and managing every port for maximum performance.
Feedback & Display
The Exigo's graphical OLED display eliminates any question as to how fast your device is charging by telling you exactly what's happening in real time. Detailed charge current, voltage and elapsed time are displayed simultaneously for all four ports. Each port also includes a multi-color RGB LED to give you color-coded status information at a glance.
We've done some initial machining to check aesthetics on the case, but have since added the OLED to the design and we've not yet integrated that into the machined prototype.
Quality & Noise
It doesn't take very much voltage noise from a charger to affect the entire device, interfering with other systems and especially sensitive analog like audio. Higher levels of noise will result in even more stress on your device. If you've ever tried to listen to music while charging your device - you've probably heard some of this yourself.
Some of the most common quality issues we've encountered with existing chargers include electrical noise, poor voltage accuracy and - in extreme examples - poor protection circuitry which can even lead to electrocution. Electrical noise is an issue common to all switching power supplies, but the level of noise found in some USB power supplies is ridiculous. We've measured more than 1000 mV of noise on some with several suffering from at least 200-300 mV. Most modern devices will survive even extreme levels of electrical noise, but long term affects are largely unknown. By contrast the combination of multi-phase technology and dedicated linear regulators in the Exigo provides the cleanest, most accurate power delivery in the industry.
Voltage accuracy is another common quality issue with USB chargers. Low voltage means your device isn't getting as much power as it should and it won't charge as quickly for two reasons:
- Low voltage means physically - less power is available
- Most devices interpret low voltage to mean the charger isn't powerful enough to draw full current safely and they will reduce charging speed even further.
If the voltage gets really low, it won't work as a charger at all. That's why it's important to precisely control the voltage output: maximizing power delivery while keeping your device safe from damage.
The trend towards small cube chargers that plug directly into the wall outlets have shrunk power electronics to their physical limits. This means the isolation between dangerous household voltages and the low voltages used to charge your portable devices is also very slim. Everything is crammed into that little cube very close together. When corners are cut and substandard designs are used to lower cost, that close proximity can become dangerous and even fatal. Fires and electrocutions from sub-standard chargers have been documented all over the world. While not a common occurrence with major brands, it's a real danger that consumers should be aware of and provides good reason to avoid cheap imitation chargers. We’d like to think that everything we buy is tested by UL or certified to rigorous CE standards but unfortunately these days many manufacturers rubber stamp their products, sneak through the safety and quality systems and deliver the cheapest possible product to your door.
During our own limited performance testing - we also experienced a dangerous failure from one of the low cost chargers:
Our 66W charger has 5x the total capacity of even the largest Apple USB charger so we need to take a rather different approach to the cheap cube chargers. We utilize an external power adapter that's CE & UL listed to convert household voltage to 24VDC. Then the Exigo's patent pending internal multi-phase converter and individual regulators fine tune and filter the final supply voltage to a current limited, precision output for each and every port. This combination increases safety and quality and reduces time to market. It also means the Exigo can run directly on 12 to 24V vehicle or battery power - making it the perfect travel companion.
Apart from the negotiation issue, many chargers are rated at specifications they can't really provide. A charger may claim 2.1A current capability, but many lower the output voltage to 4.0, 3.0 or even 2.0 volts to achieve that current. Standards like the USB battery charging spec allow a deterioration to a dismal 3.6V at full current output. That's nearly a 30% reduction in power. Even if your device manages to continue charging at such low voltages (most will not), it will be unbearably slow. Our robust multi-phase converter and microprocessor controlled regulators ensure maximum power is always delivered whether your device is sipping only 0.1A or drawing the full 3.0A capacity.
Patrick Marcus, PhD
Dr. Patrick Marcus is the President of Marcus Engineering, LLC and a principal of Apparently Connected, LLC. Dr. Marcus has a bachelors of science in Electrical Engineering, cum laude, and a PhD in Biomedical Engineering with a minor in Neuroscience from the University of Arizona. Dr. Marcus is also a graduate of the McGuire Entrepreneurship Program at the Eller College of Management. Dr. Marcus has extensive background in electronics design, industrial automation, and design for manufacturing. Dr. Marcus has founded and run several successful companies in technology and high reliability industrial manufacturing.
Nathan Crum is a principal of Apparently Connected, LLC. Nathan has a bachelors of science in Mechanical Engineering from Montana State University. Nathan has extensive background in mechanical engineering, machine design, material handling and thin film vacuum coating systems. Nathan has independently designed and delivered millions of dollars of innovative new products and custom machinery in the material handling and vacuum coating industries.
Jan 2013: Concept / Project Inception
Jan-Apr 2013: Product Research
Mar-Apr 2013: Preliminary Product Specification
Mar-Dec 2013: Component Selection / Identification
Sept 2013: Provisional Patent Application
Oct 2013 - Feb 2014: Subsystem Circuit Designs
Dec 2013 - Jan 2014: Prelim MFG Quotes & Feasibility Analysis
Jan-Jun 2014: Alpha Prototype Sub-systems, Debug & Optimization
Jun-Jul 2014: Performance Testing & Design Verification
Aug-Sept 2014: Kickstarter Campaign
Sept-Oct 2014: Beta Final Circuit / Assembly / Testing
Nov 2014: Final Production Design Documented
Nov-Dec 2014: MFG Quote Packages & Vendor Selection
Dec-Feb 2015: Manufacturing and Assembly
Mar 2015: Packaging & Shipping Rewards
Risks and challenges
The development effort is far enough along that there are few technological risks left. Our only remaining concern is that the solution we've implemented is expensive. We did not cut corners on technology or quality and keeping costs in check is a challenge. So it's critical that we aggressively negotiate prices with our vetted suppliers. Our priority is also to source all assembly and manufacturing services locally and that makes it even more difficult to stay economically competitive. Cost is our last remaining hurdle to clear, but we didn't get this far without a plan for how to deliver.
The mechanical assembly is also not trivial in cost, but in higher quantities, it will not be the limiting factor. We have a diverse network of qualified machine shops we've worked with and know who to utilize to get precision parts on time and right the first time.
We've both worked in high tech manufacturing for over a decade and have a diverse network of fabricators and contract electronics manufacturers to leverage. We've already identified suppliers for key components and accessories. We have preliminary quotes for the PCB assembly and housing. All together - we have a solid plan that's ready to execute once our project is funded, but there's always surprises when it comes time to deliver and that's where our experience will keep us on track.
The most likely consequence of any unanticipated issues at this point is that it could delay final shipment. That said, there are also several ways we plan to mitigate the risk of delays by being prepared and proactive with our contract manufacturers and back-up suppliers. Given the chance, we're confident we can deliver this product to our backers and we're excited to get them into your hands.Learn about accountability on Kickstarter
The Exigo is capable of being supplied from any 12-24VDC source like a car, RV or boat, but it is a high power charger and typically will require being plugged into a household outlet. It does not have any provision for an on-board battery.
- (45 days)