Posts tagged “new products” (Page 19)
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Our family of Mini Plastic Gearmotors is growing! We have added HP versions with more powerful motors for increased torque and speed, and we are now carrying versions with extended motor shafts intended for use with custom encoders for motor speed and position feedback. (These extended-shaft versions are not compatible with the magnetic encoders we just released for our Micro Metal Gearmotors; we will have a similar encoder solution for these plastic gearmotors at some point, but for now we are offering them for people who want to make their own encoders.) The following table shows the current state of our Mini Plastic Gearmotor family:
@ 4.5 V
@ 4.5 V
@ 4.5 V
90° output + motor shaft
offset output + motor shaft
|1250 mA||150 RPM||25 oz-in||120:1 mini HP||120:1 mini HP||120:1 mini HP||120:1 mini HP|
|low-power||800 mA||120 RPM||20 oz-in||120:1 mini||120:1 mini||120:1 mini||120:1 mini|
|80 RPM||30 oz-in||180:1 mini||180:1 mini|
We are particularly excited about these gearmotors because they offer a great combination of performance and affordability; don’t be surprised if you find these motors in some of our future robots and robot kits! For more information about all of these gearmotors, see our Mini Plastic Gearmotors category.
Last month, we introduced our new carriers with Sharp GP2Y0A60SZLF analog distance sensors, a part we are very excited about and have been trying to get for the past five years. Those complete sensor modules ship with the GP2Y0A60SZLF installed on our compact carrier board, which includes all of the required external components and provides a more convenient interface to the sensor (and a mounting hole!). Well, we are now offering the carrier boards without the sensor for those who already have Sharp GP2Y0A60SZLF units and are looking for an easy way to incorporate them into their projects. The carrier boards are available in two configurations: a 5V version for operation from 2.7 V to 5.5 V and a 3V version for operation from 2.7 V to 3.6 V:
For more information, see the product pages.
Get FREE copies of Circuit Cellar magazine’s October issue and Elektor magazine’s October issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT1014 and ELEKTOR1014 into your shopping cart. Each magazine will add 6 ounces to the package weight when calculating your shipping options.
Remember the post I wrote two weeks ago about our tiny D24V25F5 voltage regulator and some of the testing that we did on it? Well, we were so happy with how that regulator turned out that we decided to make a higher-power version with a larger inductor and beefier MOSFETs. This new regulator is the D24V50F5, and while it is only 0.1″ bigger than its 2.5 A cousin, it can deliver 5 amps!
Side-by-side comparison of the 2.5A D24V25Fx (left) and 5A D24V50F5 (right) step-down voltage regulators.
You can see the bigger MOSFETs on the bottom side:
Comparison of the D24V25Fx (left) and D24V50F5 voltage regulators showing larger MOSFETs on the higher-power board.
The D24V50F5 can also take inputs up to 38V and has typical efficiencies of 85% to 95%. It’s amazing how much power these little 3×3 mm MOSFETs can handle, and with its compact size and high power, this regulator is our new favorite.
Everyone wants encoders on their motors. If you think you don’t, you just don’t know it yet. I think the main reason is that we really just want motors to do what we tell them to do, but they don’t. One of the most common beginner questions we get is some variation of, “why doesn’t my robot go straight?” or “I got two of the same motor but they do not go the same speed; is something wrong with one of them?” More seasoned robot builders know that since there will always be variations in everything that contributes to a motor’s performance, our best hope is to put a sensor on the motor to monitor what is actually happening and then adjust the motor control to make reality better match our desires. Continued…
Get FREE copies of Circuit Cellar magazine’s September issue and Elektor magazine’s September issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT0914 and ELEKTOR0914 into your shopping cart. The Circuit Cellar magazine will add 6 ounces and the Elektor magazine will add 7 ounces to the package weight when calculating your shipping options.
We recently substantially reduced prices on our stepper motor driver carriers, and I figured this announcement was a good time to give you an update on our perspective and capabilities.
It has been over five years since I designed our original stepper motor driver carrier, which was for the A4983 from Allegro. While fairly straightforward, the implementation reflected several design philosophies that go into Pololu products, such as making the boards as small as practical and including the right extra components to make the main chip easily usable without unnecessarily limiting its features. Continued…
Last December we started carrying addressable RGB LED strips based on the WS2812B LED driver. Since that driver integrates an LED and a driver into the same package, we were able to offer higher density strips than before.
We are excited to announce that we are now carrying an even higher-density WS2812B LED strip. This strip has 72 LEDs and is 0.5 m long, for a density of 144 LEDs per meter. It is also the shortest WS2812B strip we carry.
LED side of the WS2812B-based addressable LED strips, showing 30 LEDs/m (top), 60 LEDs/m (middle), and 144 LEDs/m (bottom).
A 1/2-meter, 72 LED addressable RGB LED strip on the included reel.
This LED strip, like the other WS2812B strips we carry, has both input and output JST SM connectors, which make it easy to connect multiple strips together. It is compatible with many popular microcontrollers, and we provide Arduino libraries to help you get started. More information about this LED strip, including how to use it, can be found on its product page.
You can also view our entire selection of WS2812B LED strips.
Just about every integrated switching regulator datasheet I come across advertises how easy it is to use the chip, which is probably a good sign that it’s not necessarily that easy. I have designed several of our regulator boards, and for the most part, following the manufacturer recommendations and warnings about short traces and small loops led to working designs without much drama. But, as we push for higher performance, it can get tricky, and I thought I would share some fun pictures of what goes into troubleshooting a design that ought to work but did not.
This instance is about the D24V25F5 step-down regulator we just released today. It should have been straightforward because the basic circuit is very similar to that of the higher-power D24V60F5 and D24V90F5 regulators we released earlier this year. Because this board was supposed to be really small, I designed it with components tightly packed on both sides, which meant I had to make compromises on some of those trace lengths and loop sizes. It wasn’t even clear that the circuit would be routable with just two PCB layers, so when I did find a solution, the design team wanted to try it even though we knew we were pushing our luck.
Pololu 2.5A Step-Down Voltage Regulator D24V25Fx, side view.
Well, if we had been lucky, you might have been reading a less interesting version of this new product announcement three weeks ago. As is typical for these borderline cases, it was the especially hope-dashing kind of failure where a casual test indicated that the board was working, but more in-depth tests revealed stability and performance issues. To make sure the components were not the source of the problem, we put the exact same components onto the PCB of the larger version that already worked. The pictures below show the D24V60F5 regulator (left) populated with its standard components and the D24V60F5 regulator’s PCB populated with the components for the new D24V25F5 (right).
The new components on the old board worked, so after some final checks that the new prototypes were assembled correctly, we knew it was a layout issue. We wanted assurance that the design could work before just diving into a four-layer revision, so I took some prototypes and added redundant connections to see their impact. The pictures below show some of my test boards with varying numbers of additional ground connections.
I was able to see that the more additional ground connections there were, the more the issues went away. So, I routed the four-layer board, and after a week of tests on over a dozen prototypes, I am happy to announce the release of our most sophisticated regulator yet! The D24V25F5 buck regulator generates 5 V from input voltages of up to 38 V with typical efficiencies of 85% to 95%. The board measures only 0.7″ × 0.7″, but it allows a typical continuous output current of up to 2.5 A.
We are quite happy with how manufacturing of these units is going, so we expect to be moving toward more dense designs like this in future products.