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The Hydra is a triple-output power converter from CH Robotics designed to make it easier to get the power you need for your next project. The Hydra can quickly give you access to three independent, software-configurable DC output voltages to power your system. The easy-to-use Smart Power Supply Control Software makes it quick and simple to configure and control the Hydra’s outputs from your computer via USB. Bench-top power supplies can be large and bulky, but the Hydra fits in the palm of your hand and can also be configured from a user-programmable microcontroller via serial. This flexibility makes the Hydra a great fit for a large variety of projects, whether you are building an industrial system or a small mobile robot.
For more information, see the Hydra product page.
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For other issues and more information, see our Free Elektor Magazine Offers page. All issues are now available for shipping worldwide!
After having been out of the short-range Sharp GP2D120XJ00F analog distance sensor for a while, we are happy to have a higher-performance replacement: the Sharp GP2Y0A41SK0F analog distance sensor. The newer GP2Y0A41SK0F has the same physical dimensions, pinout, and 4 cm to 30 cm operating range as the original GP2D120XJ00F, but it offers a much higher update rate and lower average current draw. This sensor is an inexpensive and easy way to add close-proximity rangefinding or obstacle detection to your electronics or robotics project.
For longer-range analog rangefinders and shorter-range digital distance sensors, check out our full selection of optical rangefinders.
Earlier this month we introduced our new line of powerful U3V50x boost regulators; now we have a similarly powerful family of S18V20x step-up/step-down voltage regulators to go along with them! We are especially excited about these regulators, which have a wide 3 V to 30 V input voltage range, typical efficiency of 80% to 90%, and maximum output current of approximately 2 A when the input voltage is near the output voltage.
Step-up/step-down regulators like the S18V20x work with input voltages that are less than, equal to, or greater than the output voltage. This makes them especially well suited for battery-powered applications where the nominal battery voltage is close to the desired output voltage, and the actual battery voltage transitions from above the output to below as the battery discharges. For example, these regulators make it possible to get a steady 12V from a 12V battery or a steady 6V from five NiMH cells, which can be over 7 V when fully charged and below 5 V when drained. These regulators are also great for applications where having a very wide operating voltage range is desirable, such as projects where you want a lot of flexibility in power supply choice or in systems powered by alternative energy sources like solar or wind, where the output voltage can vary greatly.
The S18V20x family includes versions with fixed 5 V, 6 V, 9 V, or 12 V outputs and versions with adjustable 4 V to 12 V or 9 V to 30 V outputs. All of them feature 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 compact boards (0.825″ × 1.7″) have four mounting holes for #2 or M2 screws and can be assembled with the included 5mm-pitch terminal blocks or 0.1″ header pins.
Modulated IR detectors typically used for remote control of household electronics have long been used in robot sensors because they are small, cheap, and very sensitive while still blocking out unwanted interference. However, part of what makes the modules so good for remote control is their complex automatic gain control (AGC) circuitry that adjusts the sensors’ sensitivity to ambient lighting conditions to give clean, digital outputs in a variety of environments. Unfortunately for those using the modules for other purposes, all of that magic is internal to the modules and leads to two shortcomings: we cannot know how strong the optical signal is because we do not know the gain value, and we cannot have consistent behavior because we cannot control how the AGC behaves.
So, you can imagine how excited I was to find out about Vishay’s new IR modules designed specifically for sensor applications. They have two basic versions: one with a fixed gain that is constantly super-sensitive, and another one with a predictably-varying AGC that lets you know how bright the incident IR is. We used the fixed-gain units on the IR proximity sensors we released earlier this year, and we plan to make more products that use these unique sensors. In the meantime, we are happy to offer the through-hole versions of these sensors so you can start playing around with them to make your own sensor systems. Here are the two parts:
Those IR proximity sensors I mentioned earlier work nicely with these new sensors since our boards include a high-brightness LED with a 38 kHz modulation circuit, so you can use several of those with these new IR detectors to make sophisticated sensing solutions in which you enable one emitter at a time and monitor the reflections with all the other sensors.
We’re now selling an I²C long distance differential extender from SJTbits. When you connect one of these boards to each I²C device in your system, they transparently convert all I²C communications to differential signaling and back, allowing the range of your I²C bus to be significantly increased (they have been tested at ranges of over a hundred feet).
For more information, see the I²C Long Distance Differential Extender product page.
Do you want your project to vibrate annoyingly like a cell phone? Then our new vibration motor might be just what you are looking for. The vibration motor is intended for 3 V operation and is small (11.6 × 4.6 × 4.8 mm) and light (0.8 g), which means you do not need a lot of space in your project for it. The vibration motor includes the small rubber sleeve shown in the picture, which allows for easier mounting and slightly dampens any chattering that might occur against the surface it is mounted to.
For more information, see the Vibration motor 11.6 × 4.6 × 4.8 mm product page.We also carry three shaftless vibration motors:
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.