26 November Update: We are no longer accepting doorbuster submissions. If you submitted wishes for doorbuster coupons, thank you! You should receive an email from us soon. All the sale details are now up on the Black Friday sale page.

What’s this? A 400-Point breadboard with mounting holes! We know you’ve been waiting for this your whole life.

Okay, maybe not. But hey, mounting holes are awesome, and now you can pick up some of our new 400-point breadboards and mount them all over the place!

This 3.2″ × 2.1″ breadboard is fairly standard in many ways. It has four bus lines spanning the length of the board and 30 rows of pins, enough for up to four 14-pin DIP ICs or three 16-pin DIP ICs. The rows and columns of tie points are conveniently labeled, multiple units can be connected for larger projects, and it has an adhesive backing for those of you who like sticking breadboards on things.

But this breadboard is also a little special. It has eight mounting holes for M2 or #2 screws spaced evenly down the center on a 1 cm pitch. Now you can do stuff like mount your breadboard to a Romi Chassis (or any robot chassis) with some standoffs like this:

Wow! So convenient! And they’re just $2.49 each! But, even better, we’ve got a special discounted price for the first hundred customers. Get up to 10 boards at just $1.75 each using coupon code 400PTBBINTRO!

Related products

	Pololu 400-Point Breadboard with Mounting Holes
	Romi Chassis Kit - Red

Looking to make an awesome Halloween costume or impressive yard display? Well, we want to help, so we’re having a sale through Wednesday, October 23 on hundreds of items you can use to make things that will impress or terrify your friends and neighbors! Visit the sale page for more information, and if you are in need of some inspiration, check out our Halloween-tagged blog posts for some sample projects.

By the way, we’d love to see more about the amazing things you all are building with our products, so please don’t hesitate to share them with us.

We have expanded our line of Hall effect-based linear current sensors from Broadcom to include ±40 A and ±50 A versions. These easy-to-use bidirectional current sensors are now available in five current range options:

• ACHS-7121 Current Sensor Carrier -10A to +10A
• ACHS-7122 Current Sensor Carrier -20A to +20A
• ACHS-7123 Current Sensor Carrier -30A to +30A
• ACHS-7124 Current Sensor Carrier -40A to +40A
• ACHS-7125 Current Sensor Carrier -50A to +50A

With these additions, our full line of current sensors now includes 15 options with current and sensitivity ratings ranging from ±5 A with 400 mV/A sensitivity to ±75 A with 28 mV/A sensitivity. The following table shows all of current sensor options:

	ACS709 Current Sensor Carrier	ACS711EX Current Sensor Carriers	ACS714 Current Sensor Carriers	ACS724 Current Sensor Carriers	ACHS-712x Current Sensor Carriers
Sensor IC:	ACS709	ACS711EX	ACS714	ACS724	ACHS-712x
Current range / sensitivity(1):	±75 A / 28 mV/A	±15.5 A / 136 mV/A ±31 A / 68 mV/A	±5 A / 185 mV/A ±30 A / 66 mV/A	0–⁠10 A / 400 mv/A 0–⁠30 A / 133 mV/A ±5 A / 400 mV/A ±20 A / 100 mV/A ±50 A / 40 mV/A	±10 A / 185 mV/A ±20 A / 100 mV/A ±30 A / 66 mV/A ±40 A / 50 mV/A ±50 A / 40 mV/A
Path resistance:	1.1 mΩ	0.6 mΩ	1.2 mΩ	1.2 mΩ	0.7 mΩ
Bandwidth	120 kHz	100 kHz	80 kHz	120 kHz	80 kHz
Vcc range:(1)	3 V–5.5 V	3 V–5.5 V	4.5 V–5.5 V	4.5 V–5.5 V	4.5 V–5.5 V
Size:	0.82″ × 0.9″	0.7″ × 0.8″	0.7″ × 0.8″	0.7″ × 0.8″	0.7″ × 0.8″
Special features:	configurable over-current threshold, low-voltage operation, high bandwidth	over-current fault pin, low-voltage operation		Differential Hall sensing rejects common-mode fields, high bandwidth
1-piece price:	$14.95	$3.95	$19.95	$11.95	$6.95
1 Sensitivity based on when Vcc is 5V.

Introductory special

As usual, we are offering an extra introductory special discount on the ACHS-712x current sensor carriers, to help share in our celebration of releasing a new product. The first hundred customers to use coupon code ACHSINTRO can get up to five units for just $3 each!

Related products

	ACHS-7121 Current Sensor Carrier -10A to +10A
	ACHS-7122 Current Sensor Carrier -20A to +20A
	ACHS-7123 Current Sensor Carrier -30A to +30A
	ACHS-7124 Current Sensor Carrier -40A to +40A
	ACHS-7125 Current Sensor Carrier -50A to +50A

We have some big announcements related to our 37D Metal Gearmotors to share! First, we now have new versions of our 37D gearmotors that feature helical pinion gears and first mating gears as seen in the photo on the left above. The helical gears help reduce vibrations, making the gearbox a little quieter and more efficient than the original versions that used all spur gears. The performance is otherwise unchanged, and the dimensions are the same, so the new versions with helical pinion gears can be used as direct replacements for the original units. We are using new product numbers for the new versions so you can know exactly which one you are getting, and the product numbers for the original spur versions are being phased out. The following table shows all of the new helical-pinion versions:

Rated Voltage	Stall Current	No-Load Current	Gear Ratio	No-Load Speed (RPM)	Extrapolated Stall Torque		Max Power (W)	Without Encoder	With Encoder
					(kg ⋅ cm)	(oz ⋅ in)
12 V	5.5 A	0.15 A	1:1 (no gearbox)	10,000	0.5	7	–	–	item #4750
			19:1	540	8.5	120	12	item #4741	item #4751
			30:1	330	14	190	12	item #4742	item #4752
			50:1	200	21	290	10	item #4743	item #4753
			70:1	150	27	380	10	item #4744	item #4754
			100:1	100	34	470	8	item #4745	item #4755
			131:1	76	45	630	6	item #4746	item #4756
			150:1	67	49	680	6	item #2829	item #2828

We have also expanded the 37D gearmotor line by adding a new 150:1 gear ratio, which becomes our new highest gear ratio offering for this line of gearmotors. This version has an extrapolated (i.e. theoretical) stall torque of 49 kg⋅cm (680 oz⋅in), but please keep in mind that the point of high gear ratios like this is not to allow for more total torque. Rather, they enable slower speeds and draw less current than lower gear ratios for the same loads. For all of our 37D gearmotors, we recommend keeping continuously applied loads under 10 kg⋅cm (150 oz⋅in) and instantaneous torques under 25 kg⋅cm (350 oz⋅in).

Finally, we now have published performance graphs (1MB pdf) for our 37D gearmotors, just like the ones we previously released for our Micro Metal Gearmotors and our 20D Gearmotors! Each chart is based on hundreds of individual measurements that reveal how the speed, current, power, and efficiency of that particular gearmotor version depend on the applied load (i.e. torque).

37D mm metal gearmotor undergoing dynamic performance testing.

These characterizations are yet another way we set our gearmotors apart from the many similar-looking alternatives out there. When you get your gearmotors from us, you know exactly what kind of performance to expect, and because we make and test them ourselves, you can count on getting that same performance batch after batch after batch.

If you have any questions or feedback about these graphs or if there is additional information you would like to see available for our motors, please feel free to contact us (or just leave a comment below). And if you are wondering about graphs for 25D Gearmotors, don’t worry, those are coming! (If you need something before those datasheets are done, just let us know and we might be able to get you preliminary data for a particular gearmotor.)

Performance summary table from 37D mm Metal Geamotor datasheet.

Related products

	150:1 Metal Gearmotor 37Dx57L mm 12V (Helical Pinion)
	150:1 Metal Gearmotor 37Dx73L mm 12V with 64 CPR Encoder (Helical Pinion)

We are having a Labor Day sale through Tuesday, September 3! Check out the sale page for more information. Please note that we will be closed Monday, September 2, so orders placed after 2 PM Pacific Time Friday, August 30th will be shipped on Tuesday, September 3.

Pablo Lewin wanted a way to adjust the antenna for his Ham radio remotely, but was told his antenna controller was too old to upgrade for remote operation. That didn’t deter him though! He got creative and came up with a solution by connecting a stepper motor to his antenna controller and then using one of our Tic Stepper Motor Controllers. Now he can access the computer the Tic is connected to remotely and control the antenna’s position through the Tic’s software. Check out the video below to see his setup:

Here’s the video Pablo recommends at the beginning of his explanation to get up and running with your own Tic Stepper Motor Controller:

Related products

	Tic T825 USB Multi-Interface Stepper Motor Controller (Connectors Soldered)
	Stepper Motor: Bipolar, 200 Steps/Rev, 42×38mm, 2.8V, 1.7 A/Phase
	Pololu Stamped Aluminum L-Bracket for NEMA 17 Stepper Motors
	Pololu Universal Aluminum Mounting Hub for 5mm Shaft, #4-40 Holes (2-Pack)

We are having an Independence Day sale from now through Monday, July 8! Check out the sale page for more information. Please note that we will be closed Thursday, July 4, so orders placed after 2 PM Pacific Time Wednesday, July 3 will be shipped on Friday, July 5.

We now have published performance graphs (1MB pdf) for our 20D Metal Gearmotors! Each chart is based on hundreds of individual measurements that reveal how the speed, current, power, and efficiency of that particular gearmotor version depend on the applied load (i.e. torque). Our test methodology is the same as the one we used to make our Micro Metal Gearmotor performance graphs, so you can see our blog post about that for more information.

20D mm metal gearmotor undergoing dynamic performance testing.

These characterizations are yet another way we set our gearmotors apart from the many similar-looking alternatives out there. When you get your gearmotors from us, you know exactly what kind of performance to expect, and you can count on getting that same performance batch after batch after batch.

If you have any questions or feedback about these graphs or if there is additional information you would like to see available for our motors, please feel free to contact us (or just leave a comment below). And if you are wondering about graphs for our larger gearmotors, don’t worry, those are coming! (If you need something before those datasheets are done, just let us know and we might be able to get you preliminary data for a particular gearmotor.)

Performance summary table from 20D mm Metal Geamotor datasheet.

Pololu High-Power Stepper Motor Driver 36v4 (md38a) with large stepper motor.

I am very excited to announce the release of our new High-Power Stepper Motor Driver 36v4, our most powerful stepper motor driver yet, with more than twice the current capabilities of any of our alternative drivers. This driver can deliver a continuous 4 A per phase without any heat sinks or active cooling, and up to 6 A with cooling! This means we finally have a driver capable of powering our largest stepper motors like this beefy motor with a 2.8 A current rating.

This new driver also has a wide 8 V to 50 V operating range, making it great for use in 12, 24, or 36 V systems. And though you might be thinking that your stepper motor’s voltage rating is well below that max voltage so what do you care, keep in mind that running you stepper motor at a higher voltage while actively limiting the current (as you can do with all our stepper motor drivers) allows you to achieve higher step rates than you could using the rated voltage.

Other exciting features of this driver include nine different step resolutions down to 256 microsteps, STALL and BEMF (back EMF) outputs that enable more advanced control algorithms, and highly adjustable decay parameters and modes for creating ultra-smooth motion profiles. The driver is configurable through its SPI interface, and our Arduino library and example sketches can help you get started.

As usual, we are offering an extra introductory special discount on the High-Power Stepper Motor Driver 36v4 to help share in our celebration of releasing a new product. The first hundred customers to use coupon code HPSMDINTRO can get up to three units for just $8.95 each!

Related products

Pololu High-Power Stepper Motor Driver 36v4