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This week we started selling new addressable RGB LED strips. These LED strips are a great way to add some color to a project, and I would like to show a little bit about how they work. Here is a close up showing one segment of a new LED strip:
At first glance, it is easy to see the RGB LED and a capacitor, but where are all the other components, such as the LED driver? Well, let’s look more closely at the LED:
The LED actually has a driver built into it, which is the large brown rectangle in the picture. This driver receives high-speed color data, storing the first 24 bits it sees and passing the rest of the bits down the strip to the next LED. The driver is connected with tiny wires to the red, green, and blue LEDs. For the photos above, we turned each of the LEDs on at its dimmest setting so you can see their colors. This integrated circuit (IC) consisting of an RGB LED and a driver is called the WS2812B.
Since the WS2812B integrates an LED and a driver into the same package, we are able to offer higher density strips than before. We offer these WS2812B LED strips that have 60 LEDs per meter:
We also offer these WS2812B LED strips that have 30 LEDs per meter:
All of our example code has been updated to fully support the new strips. We provide example code for the Arduino, AVR, and mbed microcontroller platforms. More information about the LED strips and how to use them can be found on the LED strip product page.
Are you having trouble mounting things to 1/4″ motor shafts? These new versions of our universal mounting hubs fit most 1/4″ shafts, including round and “D” shafts. Similar to our existing universal mounting hubs for 6 mm shafts, these hubs are sold in packs of two and come with two set screws each (4 total) and the appropriate Allen wrench. These new hubs are compatible with our NEMA 23 stepper motors and come in two different versions: the Universal Aluminum Mounting Hub for 1/4″ shaft, with #4-40 mounting holes or the Universal Aluminum Mounting Hub for 1/4″ shaft, with M3 mounting holes.
Get a FREE copy of Elektor magazine’s December issue with your order while supplies last. To get your free issue, enter the coupon code ELEKTOR1213 into your shopping cart. The magazine will add 5 ounces to the package weight when calculating your shipping options.
For other issues and more information, see our Free Elektor Magazine Offers page. All issues are now available for shipping worldwide!
As you might have noticed from some of our recent blog announcements, we are steadily working on expanding our selection of hobby servos, and the latest example is Power HD’s new giant-scale (also called 1/4-scale) 1235MG servo. When compared to the popular, standard-size high-torque 1501MG servo, it is easy to see why this is called a “giant” servo:
What you get for the increased size is increased power — a huge 560 oz-in (40 kg-cm) of torque at 7.4 V or 490 oz-in (35 kg-cm) at 6 V. Previously, if you needed more torque than our high-performance standard-size servos could deliver, our only options were the Torxis monster servos; now, the 1235MG servo helps fill that power gap.
For more information, see the 1235MG servo product page.
We have included this servo in our Black Friday sale (along with the rest of our Power HD servos) for 25% off, but the sale ends tonight at midnight (PST), so you need to hurry if you want to get it at the sale price!
We are now carrying three high-performance servos from Power HD that offer an excellent combination of strength and speed for their size.
Power HD Low-Profile Digital Servo 1207TG – This servo is very fast and strong, despite being much shorter than a standard-size servo, making it great for applications with tight space constraints.
Power HD Digital Servo 8312TG – Much stronger than the 1207TG while nearly as fast, this servo is great for applications that require both high speed and high torque. All of the gears are made of titanium-shielded aluminum.
Power HD High-Torque, High-Voltage Digital Servo 1218TH – With a whopping 290 oz*in (21 kg*cm) of torque, this is our strongest standard-size servo, and unlike most hobby servos, it has an operating voltage range of 6 V to 7.4 V. Like the 8312TG, this servo has gears made of titanium-shielded aluminum.
All three of these servos feature coreless motors, all-metal gears, and digital control electronics, and all of them support pulse frequencies up to 333 Hz. For our full selection of Power HD servos (which are on sale right now for Black Friday for 25% off!), see our servo category.
As smartphones and tablets become more popular and more advanced, they drive the rapid development of progressively better and cheaper inertial sensors, and we’ve come to expect a new 3D compass/accelerometer chip from ST every year or so. We’re catching up again with their latest technology (for the time being) with the release of our LSM303D 3D compass and accelerometer carrier.
The LSM303D offers a number of improvements over its predecessors, including a wider maximum magnetic sensing range (up to ±12 gauss). It also features a more unified I²C interface and adds support for SPI communication. Our carrier board includes a 3.3 V voltage regulator and level shifters that make it easy to use with 5 V systems. For more information, see the product page.
We are now carrying the Raspberry Pi Model B, Revision 2.0!
In case you haven’t heard of the Raspberry Pi, it is a popular credit card-sized computer that can run Linux. It was designed by the Raspberry Pi Foundation in order to provide an affordable platform for experimentation and education in computer programming. The Raspberry Pi can be used for many of the things that a normal desktop PC does, including word-processing, spreadsheets, high-definition video, games, and programming. With its 0.1″-spaced GPIO header and small size, the Raspberry Pi also works as a programmable controller in a wide variety of robotics and electronics applications. We have seen a lot of our customers do neat things with the Raspberry Pi, and we have featured several of those projects on this blog.
Related past posts featuring the Raspberry Pi:
For more information on the Raspberry Pi, see the product page.
Our 75:1 HP micro metal gearmotor is now available with an extended motor shaft that works with our recently released optical quadrature encoders. If there are other gear ratios that you would like to see available with extended motor shafts, we would love to hear about it.
When properly modified for continuous rotation, hobby RC servos become an inexpensive, compact, easy-to-use actuator system for robotics projects, and servo manufacturers are increasingly answering the growing demand for such products with servos designed specifically for robots. One example is Power HD’s new AR-3606HB continuous rotation servo, which offers open-loop speed control rather than the closed-loop position control you typically get with a servo. It is the fastest and strongest continuous rotation servo we carry (up to 71 RPM and 93 oz*in of torque), with performance well suited for driving a small robot.
These basic boards conveniently break out the VBUS, GND, D-, D+ and ID pins of USB Mini-B and Micro-B connectors to a set of five 0.1″-spaced pins, making it easy to power your project from a USB port or to add a USB connector to your breadboarded USB microcontroller. The compact USB Mini-B Connector Breakout Board measures 0.55" × 0.85", while the even smaller USB Micro-B Connector Breakout Board measures 0.44" × 0.5" (including the USB connectors).
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