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Ever since the release of our original adjustable boost regulators, customers have been requesting higher-power versions. Doing power systems right is not easy, and minute differences in component choices and layout can make a huge difference in performance: we went through three different failed designs before arriving at our new U3V50x family of step-up voltage regulators, which we think offers a great balance of size, performance, and price.
These new boost regulators can generate up to 30 V from input voltages as low as 2.9 V while allowing for input currents as high as 5 A and offering typical efficiencies of 80% to 95%, making these our most powerful boost regulators. The regulators include built-in reverse-voltage protection, over-current protection, thermal shutdown, and an under-voltage lockout that keeps the modules from behaving erratically when the input voltage gets too low. The U3V50x family includes versions with fixed 5 V, 6 V, 9 V, 12 V, or 24 V outputs and versions with adjustable 4 V to 12 V or 9 V to 30 V outputs.
The compact boards (0.6″ × 1.9″) have two mounting holes and can be assembled with the included 5mm-pitch terminal blocks or 0.1″ header pins.
If you’re looking for an inexpensive motor driver that works with higher voltages, but our DRV8801 carrier’s single channel isn’t enough, we now offer another option: a carrier board featuring Allegro’s A4990 dual motor driver.
The A4990 can deliver a continuous current of up to 0.7 A per channel at voltages from 6 to 32 V, making it a good choice for small, low-current motors that run on relatively high voltages. Onboard sense resistors enable the A4990 to actively limit the peak motor current to about 0.9 A per channel, and the carrier board adds a reverse-voltage protection circuit in addition to the robust IC’s built-in protection against under-voltage, over-voltage, over-temperature, and short circuits.
For more information, see the A4990 carrier product page.
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.