We love motors here at Pololu, and we are committed to offering you the best selection so that you can find just the right drive solution for your project. Our latest efforts have gone into expanding our selection of 20D gearmotors to include 12 V versions, which have approximately the same performance at 12 V as our 6 V versions do at 6 V, just with half the current draw. This in turn enables the use of lower-current (and typically lower-cost) motor drivers in applications with access to higher voltages.

Additionally, we noticed that our original 6 V versions do not last as long as we would like in some applications, so we made these new 12 V versions with long-life carbon brushes instead of precious metal brushes, and we released new versions of our 6 V motors with long-life carbon brushes as well. These versions have “CB” in their names, and they can be differentiated from versions with precious metal brushes by their copper-colored terminals.

20D mm metal gearmotor precious metal brushes (left) next to 20D 6V CB and 12V CB long-life carbon brushes.

Please note that making the brushes more robust can just move the failure point to the windings or gears if you try to push the motors too hard, but if you use them around their nominal voltages and keep the continuous load low (under around 20% of the stall torque or 1 kg-cm, whichever is lower), the carbon brushes allow the motors to last several times longer than versions with precious metal brushes.

Changing the brushes does affect the performance in ways beyond lifetime (e.g. the starting voltage is generally a little higher with the carbon brushes), so we are continuing to offer precious metal versions of our 6 V motors for now, but we might phase those out in the future. Please contact us or post a comment below if continued availability of the precious metal versions is important to you.

Currently, only the 6V versions with precious metal brushes are available with a rear motor shaft that can be used to add an encoder, like our magnetic encoder for 20D mm metal gearmotors, but the 6V CB and 12V CB motors should be available with this rear shaft option by the end of November.

With the addition of these new units, our selection of 20D gearmotors now spans nearly fifty options:

Rated Voltage	Brush Type	Stall Current @ Rated Voltage	No-Load Speed @ Rated Voltage	Approximate Stall Torque @ Rated Voltage	Single-Shaft (Gearbox Only)	Dual-Shaft (Gearbox & Motor)
12 V	long-life carbon (CB)	1.6 A	570 RPM	26 oz-in	25:1 12V CB
			450 RPM	33 oz-in	31:1 12V CB
			225 RPM	58 oz-in	63:1 12V CB
			180 RPM	75 oz-in	78:1 12V CB
			140 RPM	85 oz-in	100:1 12V CB
			110 RPM	110 oz-in	125:1 12V CB
			90 RPM	130 oz-in	156:1 12V CB
			72 RPM	160 oz-in	195:1 12V CB
			57 RPM	200 oz-in	250:1 12V CB
			45 RPM	250 oz-in	313:1 12V CB
			36 RPM	290 oz-in	391:1 12V CB
			29 RPM	350 oz-in	488:1 12V CB
6 V	long-life carbon (CB)	2.9 A	590 RPM	22 oz-in	25:1 6V CB
			470 RPM	28 oz-in	31:1 6V CB
			230 RPM	54 oz-in	63:1 6V CB
			190 RPM	62 oz-in	78:1 6V CB
			150 RPM	72 oz-in	100:1 6V CB
			120 RPM	87 oz-in	125:1 6V CB
			93 RPM	110 oz-in	156:1 6V CB
			75 RPM	130 oz-in	195:1 6V CB
			60 RPM	170 oz-in	250:1 6V CB
			46 RPM	220 oz-in	313:1 6V CB
			37 RPM	260 oz-in	391:1 6V CB
			30 RPM	310 oz-in	488:1 6V CB
6 V	precious metal	2.9 A	590 RPM	22 oz-in	25:1 6V	25:1 6V dual-shaft
			470 RPM	28 oz-in	31:1 6V	31:1 6V dual-shaft
			230 RPM	54 oz-in	63:1 6V	63:1 6V dual-shaft
			190 RPM	62 oz-in	78:1 6V	78:1 6V dual-shaft
			150 RPM	72 oz-in	100:1 6V	100:1 6V dual-shaft
			120 RPM	87 oz-in	125:1 6V	125:1 6V dual-shaft
			93 RPM	110 oz-in	156:1 6V	156:1 6V dual-shaft
			75 RPM	130 oz-in	195:1 6V	195:1 6V dual-shaft
			60 RPM	170 oz-in	250:1 6V	250:1 6V dual-shaft
			46 RPM	220 oz-in	313:1 6V	313:1 6V dual-shaft
			37 RPM	260 oz-in	391:1 6V	391:1 6V dual-shaft
			30 RPM	310 oz-in	488:1 6V	488:1 6V dual-shaft

Note: Stalling or overloading gearmotors can greatly decrease their lifetimes and even result in immediate damage. In order to avoid damaging the gearbox, we recommend keeping continuously applied loads under 50 oz-in (3.5 kg*cm) for the versions with precious metal brushes and under 70 oz-in (5 kg-cm) for the versions with carbon brushes (the ones with “CB” in the name). Stalls can also result in rapid (potentially on the order of a second) thermal damage to the motor windings and brushes, especially for motors like this that can deliver a lot of power for their size; a general recommendation for brushed DC motors is to limit continuous current to approximately 25% of the stall current.

Get a FREE copy of Circuit Cellar magazine’s October 2017 issue issue with your order, while supplies last. To get your free issue, enter the coupon code CIRCUIT1017 to your shopping cart, or click the link. The magazine will add 6 ounces to your order weight when calculating your shipping options.

For back issues and more information, see our free Circuit Cellar magazine offers.

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Free Circuit Cellar magazine October 2017

Premium Jumper Wire 60-Piece 6-Color Assortment M-F 2".

Wires with Pre-crimped Terminals 60-Piece 6-Color Assortment M-F 2".

Our popular premium jumper wires and wires with pre-crimped terminals are a convenient way to make quick, neat connections to 0.1″ (2.54 mm) connectors and solderless breadboards, and they are now available in shorter 1″ and 2″ lengths. Each new length is available in three gender combinations (female-female, male-female, and male-male) and seven color combinations:

• black 10-pack
• red 10-pack
• yellow 10-pack
• green 10-pack
• blue 10-pack
• white 10-pack
• multi-color 60-pack (10 each of all six colors)

Our wires with pre-crimped terminals work with our 0.1″ crimp connector housings to make custom cables with the pin arrangement of your choosing. You can easily make cable harnesses or assemblies that branch from one connector on one side to multiple connectors on the other, and you can also cut off one pre-crimped end and solder the wires directly to components to make swapping connections easy:

The premium jumper wires are just wires with pre-crimped terminals that have 1×1 crimp connector housings already installed over the crimp pins.

You can use the following selection boxes to get to a specific pack of premium jumper wires:

Alternatives available with variations in these parameter(s): gender length color Select variant…

and you can use the following selection boxes to get to a specific pack of wires with pre-crimped terminals:

Alternatives available with variations in these parameter(s): gender length color Select variant…

Pololu 22T Track Set – Red.

We have replaced our original Pololu track sets with new versions featuring our newer style of spoked Zumo sprockets. The sprockets are available in three colors, and like our original sets, we have two different track lengths to choose from:

• 22T tracks with black sprockets
• 22T tracks with red sprockets
• 22T tracks with white sprockets
• 30T tracks with black sprockets
• 30T tracks with red sprockets
• 30T tracks with white sprockets

Each track is made of a single piece of flexible silicone, and the drive sprockets are designed to work with 3mm D-shafts, such as those on our micro metal gearmotors and most of our mini plastic gearmotors.

Dimensions of the Pololu 22T track set.

Dimensions of the Pololu 30T track set.

Additionally, we are offering sprockets by themselves (without tracks or fasteners) for use as replacements for the black sprockets included with our Zumo robots: you can use the red sprockets to add a splash of color, and you can use the white sprockets for painting (or just leave them white!).

Zumo 32U4 robot with red sprockets.

Zumo 32U4 robot with white sprockets.

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	Pololu 22T Track Set - Black
	Pololu 22T Track Set - Red
	Pololu 22T Track Set - White
	Pololu 30T Track Set - Black
	Pololu 30T Track Set - Red
	Pololu 30T Track Set - White
	Replacement Sprocket Set for Zumo Chassis - Red
	Replacement Sprocket Set for Zumo Chassis - White

We are having a Labor Day sale all weekend long with site-wide discounts of up to 25%! Check out the sale page for more information. Please note that we will be closed Monday, so orders placed after 2 PM Pacific Time today (Friday, September 1) will be shipped on Tuesday, September 5.

In celebration of Independence Day (July 4th), we are discounting selected products by up to 25% and offering an upgrade to the next best price break for everything else in our store. Please note that we will be closed Tuesday, so orders placed after 2 PM Pacific Time on Monday, July 3 will be shipped on Wednesday, July 5.

For more information, including all the discount coupon codes, see the sale page.

Happy 4th of July!

We are having a big Memorial Day sale now through Tuesday, with discounts on over 1000 products when you use the coupon code MEMORIALDAY17. Stock up on robot parts now so you can build cool things all summer long! Note that we will be closed on Monday, so orders will not ship until Tuesday, May 30.

For more information, including all of the sale items, see the sale page.

Get a FREE copy of Circuit Cellar magazine’s April 2017 issue issue with your order, while supplies last. To get your free issue, enter the coupon code CIRCUIT0417 to your shopping cart, or click the link. The magazine will add 6 ounces to your order weight when calculating your shipping options.

For back issues and more information, see our free Circuit Cellar magazine offers.

Related products

Free Circuit Cellar magazine April 2017

We’re happy to announce that our previously discontinued addressable through-hole RGB LEDs are once again part of our catalog and in stock! While these might look like ordinary RGB LEDs, each one contains its own integrated WS2811 LED driver that lets you chain them together and individually control them all with a single digital output from a microcontroller. The interface is very similar to that of our SK6812-based LED strips, so there is a variety of sample code available for the Arduino, AVR, and mbed microcontroller platforms.

The LEDs are available in two sizes: 5 mm and 8 mm.

Two different sizes of addressable RGB LED. From left to right, their diameters are: 5 mm (#2535) and 8 mm (#2536).

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	Addressable Through-Hole 5mm RGB LED with Diffused Lens, WS2811 Driver (10-Pack)
	Addressable Through-Hole 8mm RGB LED with Diffused Lens, WS2811 Driver (10-Pack)

Our newest step-up/step-down voltage regulator, the S9V11F5, takes input voltages between 2 V and 16 V and increases or decreases that voltage as necessary to produce a fixed 5 V output with a typical efficiency of over 90%. (Note that it requires a minimum of 3 V to start up, but it can operate down to 2 V once it is running.) It can temporarily deliver peaks of around 2 A, and the maximum continuous output current depends on the input voltage as shown in the graph below:

The ability to raise or lower the input voltage makes this regulator especially well suited for battery-powered applications where the nominal battery voltage is close 5 V, such as when using four NiMH cells, since the battery voltage transitions from above 5V to below as the battery discharges. The wide input voltage range is also great for applications where you want a lot of flexibility in power supply choice or for systems powered by alternative energy sources like solar or wind, where the output voltage can vary a lot.

With a wider input voltage range and its ability to deliver more current, the S9V11F5 is a higher-performance alternative to our popular S7V7F5 buck-boost regulator, all while being even smaller in size thanks to its double-sided assembly.

For more information on this regulator, visit the S9V11F5 product page, and for other regulator options, you can take a look at our full selection of step-up/step-down regulators, step-up voltage regulators, and step-down voltage regulators.

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	5V Step-Up/Step-Down Voltage Regulator S9V11F5
	Pololu 5V Step-Up/Step-Down Voltage Regulator S7V7F5