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Continuing with our recent LED product line expansion, we now offer several of Adafruit’s NeoPixel rings. These addressable RGB LED rings are available in a 1.75″-diameter 16-LED ring, a slightly larger 24-LED ring, and as 15-LED quarter-rings that can be assembled into a large 60-LED ring.
The NeoPixels are effectively WS2812B RGB LEDs that are individually addressable and controllable by a single digital pin from a microcontroller. Multiple rings can be chained together, and the rings can be chained with our other WS281x-based LED products. The animated picture below shows the three different sizes of rings we carry connected in a single chain and controlled by a single pin from an A-Star 32U4 Micro, which is small enough to fit completely within the smallest ring.
I love LEDs and all of the shiny, blinky, colorful things you can do with them (see what we did to my house last Christmas), so you can imagine how happy it makes me that we are now carrying Adafruit’s NeoPixel Shield for Arduino! With 40 individually addressable, WS2812B-based RGB LEDs all controlled by a single Arduino pin, this shield is effectively like a grid version of our addressable RGB LED strips. And just like our LED strips, multiple NeoPixel shields can be chained together into larger arrays. Controlling the LEDs is easy with the help of the compatible Arduino libraries, which include the Adafruit NeoPixel and NeoMatrix libraries, as well as our Arduino library for addressable RGB LED strips. This shield is a great way to add color, style, or functionality to your next Arduino project!
For more information on the NeoPixel shield, see the product page.
Get FREE copies of Circuit Cellar magazine’s June issue and Elektor magazine’s June issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT0614 and ELEKTOR0614 into your shopping cart. Each magazine will add 6 ounces to the package weight when calculating your shipping options.
Continuing with our recent theme of tiny new actuators, we are now carrying FS90R micro continuous rotation servos from FEETECH. Continuous rotation servos are standard hobby RC servos that have been modified for open-loop speed control instead of their usual closed-loop position control, and they make convenient drive systems for robots because they are effectively a motor, gearbox, and motor controller/electronic speed control (ESC) in a single compact package. They are also very easy to use as they can be connected directly to an RC receiver or controlled by a single microcontroller I/O line programmed to output RC servo pulses.
With a weight of just 9 g, the FS90R is the smallest servo we have come across that is manufactured specifically for continuous rotation. It has great speed and torque for its size (up to 130 RPM and 1.5 kg-cm at 6 V), and at only $5 per servo, it is a very simple and affordable way to add some motion to your next project. For comparison (or if you are looking for an alternative servo that offers position control), it is very similar in size, weight, speed, and torque to the Power HD Micro Servo HD-1900A.
For more information on the FS90R micro continuous rotation servo, see the product page. For other options, you can check out our full selection of continuous rotation servos or our entire RC servo category.
A few months ago, we introduced our new D24V5Fx buck (step-down) voltage regulator family with inaugural members offering fixed output voltages of 3.3 V, 5 V, 9 V, and 12 V, and now we have expanded that family by adding versions with fixed output voltages of 1.8 V, 2.5 V, 6 V, and 15 V.
We are particularly excited about this regulator family because of its wide operating voltage range, high efficiencies, and low dropout voltages, all in a compact 0.5″ × 0.4″ × 0.1″ (13 mm × 10 mm × 3 mm) form factor that is smaller than standard through hole linear regulators with DIP packages. For example, the picture below shows a D24V5Fx next to a 7805 voltage regulator in a TO-220 package:
These regulators operate at up to 36 V, making them especially useful in applications where there can be large variation in the input voltage, such as solar-powered systems or devices where power supply flexibility is a benefit. Since they are switching regulators, the efficiency is much higher than linear regulators when there is a big difference between the input and output voltage, and since they are synchronous, the efficiency is high even at light loads and low output voltages. As an example of the versatility of these regulators, the same D24V5F2 module can in one application be used to get 2.5 V from a 24 V battery and in another be an efficient way to add a 2.5 V node to a system that already has regulated 5 V. As the performance graph below shows, typical efficiency in the latter scenario is 90%, which could almost double battery life in portable systems when compared to linear regulators.
We consider the new D24V5Fx regulators to be next-generation alternatives to our D24V3Fx and D24V6Fx buck regulators, which have been some of our most popular products. In addition to having generally higher efficiencies (which in practice allow these 500 mA units to achieve maximum output currents comparable to our 600 mA D24V6Fx units), these new regulators have much lower dropout voltages (“dropout voltage” is the amount by which the input voltage must exceed the output voltage in order to ensure that the target output can be achieved). For example, the two graphs below show the dropout voltage of the new 5 V D24V5F5 compared to the older 5 V D24V6F5 and D24V3F5:
What this means for your project is broader operating ranges and longer battery life. For instance, a low-power 5 V system running on a 9 V battery can discharge it all the way to 5 V whereas the higher-dropout D24V6F5 regulator can only go to 6.5 V, and four-cell alkaline and five-cell NiMH packs (both with 6.0 V nominal voltages) become viable options.
We are now carrying metal servo horns that work with Power HD’s ultra-high-torque HD-1235MG giant servos, which can deliver a whopping 560 oz-in (40 kg-cm) at 7.4 V. If you want to get the most power out of your HD-1235MG, I recommend substituting one of these anodized aluminum horns for the included plastic horns.
Get FREE copies of Circuit Cellar magazine’s May issue and Elektor magazine’s May issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT0514 and ELEKTOR0514 into your shopping cart. The magazines will add 6 ounces and 7 ounces, respectively, to the package weight when calculating your shipping options.
Inevitably, if you work with electronics long enough, you will encounter a wire that is too long, too insulated, or too connected (to the wrong thing), and while you might be able to MacGyver your way out of the situation with a pair of scissors or a suitably hardy set of teeth, nothing beats a good wire stripper. With that in mind, we set off in search of some good, basic wire strippers that would get the job done well without breaking the bank. Our favorites were a set of multi-purpose wire strippers and cutters that feature comfortably curved and cushioned grips and a nose that can be used as pliers. One version works with 10 to 20 AWG wires and another works with 20 to 30 AWG wires. (The stripping holes are labeled with the gauge of solid-core wire for which they are intended; for stranded wire, use the next larger hole.)
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