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We’re excited to offer a series of APA102C-based addressable RGB LED strips to complement our existing WS2812B-based LED strips. Like the WS2812 strips, the new strips have connectors on both ends to make chaining easy, and they are available in the same six combinations of LED densities and lengths:
- 1 meter, 30 LEDs (30 LEDs/m)
- 2 meters, 60 LEDs (30 LEDs/m)
- 5 meters, 150 LEDs (30 LEDs/m)
- 1 meter, 60 LEDs (60 LEDs/m)
- 2 meters, 120 LEDs (60 LEDs/m)
- 0.5 meters, 72 LEDs (144 LEDs/m)
Like the WS2812B, the APA102C combines an RGB LED and driver into a single 5050-size package, allowing them to be packed as densely as 144 LEDs per meter, and each pixel can be individually addressed to give you full control over the color of each RGB LED. However, while the WS2812B uses a high-speed one-wire control interface with strict timing requirements, the APA102C has a standard SPI interface, with separate data and clock signals, that lets it work with a wide range of communication rates, making it much easier to control.
For example, it isn’t easy for a Raspberry Pi to generate a control signal with the exact timings that the WS281x requires. However, an APA102 only reads its data signal on the rising edge of its clock signal, and the Raspberry Pi controls both signals, meaning it is free to bit-bang data to the LEDs as slowly (or quickly) and as irregularly as it wants. Alternatively, it’s straightforward to use the SoC’s built-in SPI peripheral to drive APA102 LEDs. Of course, both the bit-banging and hardware SPI approaches can also be used on many other devices, including A-Stars and Arduinos.
|Close up of one segment of an APA102C-based LED strip, with the red, green, and blue LEDs on at a low brightness.|
The APA102C also offers a few other improvements over the WS2812B, including a color-independent brightness control that lets you easily adjust the intensity of each LED without changing its color. Also, the color channels on an APA102C are pulse-width modulated (PWM) at a much higher frequency, making it less susceptible to flickering on camera and more suited to persistence-of-vision (POV) applications.
For more information about our APA102C-based LED strips, see their product pages.
We’re now selling the latest V5 versions of the RoboClaw 2x5A, 2x15A, and 2x30A dual motor controllers from Ion Motion Control. Like the previous V4 RoboClaws, they can drive a pair of brushed DC motors at voltages from 6 V to 34 V, but the 2x5A now has a USB serial interface (in addition to TTL serial, RC, and analog inputs) like its larger siblings, and the 2x15A and 2x30A have a new heat sink design that should improve cooling. We expect to have updated documentation for the new versions soon.
We are excited about our new 0.1″ terminal blocks because they can typically be soldered to PCBs in place of standard 0.1″ male and female headers, offering alternative board-to-wire connection options that can be especially convenient in cases where you know you will be dealing with stripped, unterminated wires. For example, the following picture shows an 8-pin terminal block spanning the control connections of a VNH5019 motor driver carrier:
There are some low components (e.g. resistors and capacitors) near the motor driver’s 0.1″ holes, but the terminal block is able to comfortably sit on top of them. In cases where there is not sufficient clearance from tall, nearby components, it might be possible to use the terminal blocks on the bottom side of the PCB. The following picture is an example of this, with a 4-pin terminal block used for the motor and motor power connections of a DRV8801 motor driver carrier:
And in case these pictures are giving the illusion of large PCBs rather than tiny terminal blocks, we have for your viewing pleasure a picture of these terminal blocks in a 0.1″ prototyping board (Adafruit’s Perma-Proto prototyping PCB) next to some standard 0.1″ male header pins:
These terminal blocks cannot be combined into longer strips or placed side-by-side on a 0.1″ grid, so you will need to get the exact lengths required by your application. Fortunately, we have nine lengths to choose from, from two pins through ten pins!
We now have a shorter (20 mm) 12 mm Hex Wheel Adapter for 6 mm Shaft as an alternative to our original 35 mm extended version. These adapters work well with our 37D mm metal gearmotors, allowing you to use them with many common hobby RC wheels.
|12mm Hex Wheel Adapter for 6mm Shaft connecting a Wild Thumper Wheel to a 37D mm Metal Gearmotor.|
For our full selection of these adapters, see our hex wheel adapter category.
These drivers each offer wide operating voltage ranges, with the BD65496MUV operating from as low as 2 V up to 16 V and the MAX14870 operating from 4.5 V all the way up to 36 V. They can each supply over an amp to a single, bidirectional brushed DC motor. These are the highest-performing integrated motor drivers we know of short of substantially larger units such as the MC33926 and VNH5019. For more information on these drivers, click on the related products below:
Most electronics projects (and many Pololu products) require soldering. That’s why we’re excited to offer a soldering station and other accessories that we can wholeheartedly recommend! We are now carrying Hakko soldering and desoldering tools and Hakko hand tools (cutters and pliers). We use Hakko tools in our own manufacturing, and we believe they offer a great mix of reliability, performance, and price. Continued…
We are excited to introduce new versions of our high-power micro metal gearmotors with long-life carbon brushes in place of the standard precious metal brushes:
|Micro metal gearmotor HPCB long-life carbon brushes (left) next to micro metal gearmotor HP precious metal brushes (right).|
So far, we only offer these on motors with HP windings, so the brushes being a lot more robust can just move the failure point if you try to push the motors too hard. However, if you use them at around 6 V and keep the continuous load under around 20% of the stall torque, the carbon brushes allow the HPCB motors to last several times longer than HP versions with precious metal brushes.
With the addition of this new HPCB motor variant in ten different gear ratios (10:1 through 1000:1), our selection of popular micro metal gearmotors now spans more than fifty options, giving you control over the motor winding, gearbox, and shaft arrangement:
@ 6 V
@ 6 V
@ 6 V
(Gearbox & Motor)
|1600 mA||3000 RPM||4 oz-in||10:1 HPCB|
|1000 RPM||9 oz-in||30:1 HPCB|
|625 RPM||15 oz-in||50:1 HPCB|
|400 RPM||22 oz-in||75:1 HPCB|
|320 RPM||30 oz-in||100:1 HPCB|
|200 RPM||40 oz-in||150:1 HPCB|
|140 RPM||50 oz-in||210:1 HPCB|
|120 RPM||60 oz-in||250:1 HPCB|
|100 RPM||70 oz-in||298:1 HPCB|
|32 RPM||125 oz-in||1000:1 HPCB|
(same specs as
|1600 mA||6000 RPM||2 oz-in||5:1 HP|
|3000 RPM||4 oz-in||10:1 HP||10:1 HP dual-shaft|
|1000 RPM||9 oz-in||30:1 HP||30:1 HP dual-shaft|
|625 RPM||15 oz-in||50:1 HP||50:1 HP dual-shaft|
|400 RPM||22 oz-in||75:1 HP||75:1 HP dual-shaft|
|320 RPM||30 oz-in||100:1 HP||100:1 HP dual-shaft|
|200 RPM||40 oz-in||150:1 HP||150:1 HP dual-shaft|
|140 RPM||50 oz-in||210:1 HP|
|120 RPM||60 oz-in||250:1 HP|
|100 RPM||70 oz-in||298:1 HP||298:1 HP dual-shaft|
|32 RPM||125 oz-in||1000:1 HP||1000:1 HP dual-shaft|
|700 mA||2200 RPM||3 oz-in||10:1 MP||10:1 MP dual-shaft|
|730 RPM||8 oz-in||30:1 MP|
|420 RPM||13 oz-in||50:1 MP|
|290 RPM||17 oz-in||75:1 MP||75:1 MP dual-shaft|
|220 RPM||19 oz-in||100:1 MP||100:1 MP dual-shaft|
|150 RPM||24 oz-in||150:1 MP|
|75 RPM||46 oz-in||298:1 MP|
|25 RPM||80 oz-in||1000:1 MP||1000:1 MP dual-shaft|
|low-power||360 mA||2500 RPM||1 oz-in||5:1|
|1300 RPM||2 oz-in||10:1|
|440 RPM||4 oz-in||30:1||30:1 dual-shaft|
|250 RPM||7 oz-in||50:1||50:1 dual-shaft|
|170 RPM||9 oz-in||75:1|
|120 RPM||12 oz-in||100:1||100:1 dual-shaft|
|85 RPM||17 oz-in||150:1|
|60 RPM||27 oz-in||210:1|
|50 RPM||32 oz-in||250:1|
|45 RPM||40 oz-in||298:1||298:1 dual-shaft|
|14 RPM||70 oz-in||1000:1||1000:1 dual-shaft|
In September of last year, we started carrying our Breakout Board for microSD Card, which was the first board that I ever designed and routed here at Pololu. It is a simple breakout board that gives direct access to each contact available on a microSD card socket. However, since microSD cards operate at 3.3 V, it can be tricky interfacing them with a 5 V system. To address this, we made a new version with an integrated 3.3 V regulator and level shifters. Even with the extra components (and mounting holes, which the mechanical engineers at here Pololu are always pushing for), the board is still compact, measuring only 0.94″ × 0.9″, and it breaks out all of the contacts from a microSD card socket necessary to interface with the card through its SPI bus mode interface to a single 1×9 row of 0.1″-spaced pins. This allows easy use with breadboards, perfboards, or 0.1″ connectors.
You might recognize the circuit from our A-Star 32U4 Prime controllers, which use essentially the same level shifters to interface a microSD card with an Arduino-compatible ATmeg32U4 microcontroller running at 5 V.
For more information about this breakout board, see its product page.
This new board is a Pololu carrier for ON Semiconductor’s AMIS-30543 Micro-Stepping Motor Driver, which is a high-performance stepper motor driver with advanced features not found on our other stepper motor driver carriers.
|AMIS-30543 stepper motor driver carrier, bottom view with dimensions.|
The Pololu AMIS-30543 Stepper Motor Driver Carrier breaks out all of the important pins of the driver onto breadboard-compatible 0.1"-spaced pins, with optional terminal blocks for the power and motor connections and mounting holes for a more robust setup. Our board supplies reverse protection and all the necessary circuit components for interfacing to a microcontroller.
The AMIS-30543 is rated up to 30 V and 3 A, but (as with other stepper drivers) the current rating is a theoretical maximum assuming excellent cooling. Using our board at room temperature without a heatsink, the chip can practically supply about 1.8 A per coil, more than any of our other stepper motor driver carriers.
The SPI interface of the AMIS-30543 provides many exciting features: it lets you configure microstepping (down to 1/128-step), set the current limit, select voltage slopes, change direction, disable the outputs or put the driver to sleep, monitor the micro-step position and errors, and more. Please note, however, that you cannot step the motor over SPI.
Many of our customers have asked for software current limit control, since it allows better power management. For example, consider that stepper motors counter-intuitively use their maximum current when stopped, even if there is no holding torque required. This wastes a lot of power and generates undesirable heat in the drivers and motors. In a typical application like a 3D printer, where you don’t need much holding torque, you would want to reduce the current limit to a low value during pauses. You might use a higher limit (above the continuous limit) when accelerating and an intermediate value for constant-speed motion. The SPI current limit control on the AMIS-30543 lets you do all of this in your code.
Another advanced feature is the SLA (speed and load angle) output that indicates the level of the back-EMF voltage of the motor. This is an analog signal that can be used for stall detection or closed-loop control of the torque and speed:
|AMIS-30543 stepper motor driver SLA output (green) and motor output (blue).|
It is easy to get started using our Arduino library on GitHub, which provides basic functions for configuring and operating the driver as well as access to many of the advanced features. Please visit the product page for a detailed description, wiring diagrams, the AMIS-30543 datasheet, and more.