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.

Our wide selection of stepper motor drivers has grown once again, this time with the addition of a full breakout board for Toshiba’s TB67S128FTG. The TB67S128FTG has many of the same great innovative features as the TB67S2x9FTG carriers we released last year, including Active Gain Control (AGC) for automatically reducing the current when full torque is not needed and Advanced Dynamic Mixed Decay (ADMD) for smoother, more even microsteps. On top of that, it adds features such as microstepping down to 1/128th-step and an optional serial interface. The driver offers a wide operating voltage range of 6.5 V to 44 V, and it can deliver 2.1 A per phase continuous (5 A peak) on our carrier board without any heat sink or forced air flow, making it our highest-current integrated driver (bested only by our discrete MOSFET High-Power Stepper Motor Driver 36v4).

These stepper motor driver carriers first debuted at Toshiba’s booth at Maker Faire Tokyo in August, and now that we finally have the drivers in volume, we are able to offer them to you! All of the driver’s control pins and outputs are available, so it can function as a complete evaluation board for the TB67128FTG, yet it is compact enough to integrate into actual projects without taking up an excessive amount of space:

TB67S128FTG Stepper Motor Driver Carrier, top view with labeled pinout.

Introductory special

As with all of our new product announcements, we are offering an introductory discount to make it extra easy to try out this new driver. Be among the first 100 customers to use coupon code TB67S128INTRO (click to add the coupon code to your cart) and up to three units for just $7.95 each.

Related products

TB67S128FTG Stepper Motor Driver Carrier

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:	$5.95	$3.49	$19.95	$6.95	$3.95
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

I am pleased to announce the release of the Tic 36v4 USB Multi-Interface High-Power Stepper Motor Controller, the fifth model in our line of Tic Stepper Motor Controllers. The Tic 36v4 features a discrete MOSFET stepper motor driver that can deliver up to approximately 4 A per phase, without a heat sink or forced air flow, over a broad 8 V to 50 V operating range. With the ability to provide more than twice as much current as any of our previous stepper motor controllers, this is our highest-power Tic yet, and the first that can drive the most demanding stepper motors we carry (#1474 and #1478) with their full rated current (2.8 A).

Tic 36v4 USB Multi-Interface High-Power Stepper Motor Controller controlling a #1478 stepper motor from USB.

The Tic 36v4 supports microstepping resolutions down 1/256 step, which is 8 times smaller than any previous Tic model. These new, finer microstep resolutions make it increasingly important to be able to take steps at a high speed since with microsteps that small, it takes up to 51,200 of them to complete one revolution on standard stepper motors with 200 full steps per revolution. The Tic firmware takes care of that for you: it is designed to be able to produce up to 50,000 steps per second, meaning that you can get 58 RPM out of most of our stepper motors even when using 1/256 step mode. Every power of two step mode between full stepping and 1/256 is supported, allowing you to choose the right trade-off between speed and resolution.

An oscilloscope capture showing the current through one coil of a stepper motor as the Tic 36v4 takes 25600 microsteps per second in 1/256 step mode.

By default, the Tic 36v4 uses an automatic mixed decay mode for current regulation. In this mode, it dynamically selects between fast or slow decay based on the actual coil current, allowing it to achieve extremely smooth stepping in most applications without a lot of manual tuning—especially at high microstepping resolutions. (Isn’t that a nice sine wave in the picture above?)

However, if you want more control, this Tic also gives you the option to select a fixed decay mode and adjust several timing parameters to fine-tune the current decay behavior. This can be easily done with the Tic’s free graphical configuration software.

The decay mode settings for the Tic 36v4 in the Tic Control Center software.

Like the other members of the Tic family, the Tic 36v4 makes basic speed or position control of a stepper motor easy, with lots of configurable parameters (e.g. max speed and acceleration) and support for six high-level control interfaces:

• USB for direct connection to a computer
• TTL serial operating at 5 V for use with a microcontroller
• I²C for use with a microcontroller
• RC hobby servo pulses for use in an RC system
• Analog voltage for use with a potentiometer or analog joystick
• Quadrature encoder input for use with a rotary encoder dial, allowing full rotation without limits (not for position feedback)

This video gives a brief demonstration of these interfaces in action:

The Tic 36v4 is available with connectors soldered in or without connectors soldered in. If you do not need the high-level interfaces provided by the Tic, we also offer the Pololu High-Power Stepper Motor Driver 36v4.

Here is a handy comparison chart with all five Tic stepper motor controllers:

	Tic T500	Tic T834	Tic T825	Tic T249	Tic 36v4
Operating voltage range:	4.5 V to 35 V(1)	2.5 V to 10.8 V	8.5 V to 45 V(1)	10 V to 47 V(1)	8 V to 50 V(1)
Max continuous current per phase (no additional cooling):	1.5 A	1.5 A	1.5 A	1.8 A	4 A
Peak current per phase (additional cooling required):	2.5 A	2 A	2.5 A	4.5 A	6 A
Microstep resolutions:	full half 1/4 1/8	full half 1/4 1/8 1/16 1/32	full half 1/4 1/8 1/16 1/32	full half 1/4 1/8 1/16 1/32	full half 1/4 1/8 1/16 1/32 1/64 1/128 1/256
Automatic decay selection:
Automatic gain control (AGC):
Driver IC:	MP6500	DRV8834	DRV8825	TB67S249FTG	discrete MOSFETs
Price (connectors not soldered):	$29.95	$39.95	$39.95	$49.95	$59.95
Price (connectors soldered):	$31.95	$41.95	$41.95	$51.95	$61.95

1 See product pages and user’s guide for operating voltage limitations.

Introductory special

As usual, we are offering an extra introductory special discount on the Tic 36v4, to help share in our celebration of releasing a new product. The first hundred customers to use coupon code TIC36V4INTRO can get up to five units for just $24.95! And we’ll even cover the shipping in the US!

Related products

	Tic 36v4 USB Multi-Interface High-Power Stepper Motor Controller (Connectors Soldered)
	Tic 36v4 USB Multi-Interface High-Power Stepper Motor Controller

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 have expanded our selection of specially modified FEETECH servos that have direct access to the feedback potentiometer through an extra fourth (green) wire! Several months ago, we started carrying similarly modified micro FS90-FB and standard-sized FS5103B-FB servos. Now, our larger selection includes a variety of sizes from compact sub-micro servos all the way up to ultra-high torque giant servos:

• FEETECH Sub-Micro Servo FS0403-FB with Position Feedback
• FEETECH Mini Servo FT1117M-FB with Position Feedback
• FEETECH High-Torque Servo FS5115M-FB with Position Feedback
• FEETECH Ultra-High-Torque, High-Voltage Digital Giant Servo FT5335M-FB with Position Feedback

FEETECH Sub-Micro Servo FS0403-FB with Position Feedback.

FEETECH Mini Servo FT1117M-FB with Position Feedback.

FEETECH High-Torque Servo FS5115M-FB with Position Feedback.

FEETECH Ultra-High-Torque, High-Voltage Digital Giant Servo FT5335M-FB with Position Feedback.

These new additions are special versions of the normal sub-micro FS0403, mini FT1117M, high-torque standard-size FS5115M, and ultra-high-torque giant FT5335M FEETECH servos.

The feedback voltage, which varies linearly over the servo’s range of motion by a couple of volts, is especially useful for more complex robotic applications that require monitoring the actual servo position. For example, it can be used for determining if the servo is stalled or when it has reached it’s target position. It also allows you to implement your own higher-level closed-loop position control or create servo movements by hand that you can record and play back later.

Related products

	FEETECH Sub-Micro Servo FS0403-FB with Position Feedback
	FEETECH Sub-Micro Servo FS0403
	FEETECH Mini Servo FT1117M-FB with Position Feedback
	FEETECH Mini Servo FT1117M
	FEETECH High-Torque Servo FS5115M-FB with Position Feedback
	FEETECH High-Torque Servo FS5115M
	FEETECH Ultra-High-Torque, High-Voltage Digital Giant Servo FT5335M-FB with Position Feedback
	FEETECH Ultra-High-Torque, High-Voltage Digital Giant Servo FT5335M

We have released firmware version 1.04 for the Micro Maestro 6-Channel USB Servo Controller.

This update fixes a bug where receiving any serial command via TTL serial or the Maestro’s USB virtual serial port could potentially interfere with the Maestro’s servo update routine. The servo update routine is responsible for smoothly changing the position of each servo over time while respecting the Maestro’s configurable speed and acceleration limits. Because of the bug, receiving a serial command could cause position updates for some servos to happen too soon or to be skipped entirely. Repeated serial commands at high baud rates could also trap the Maestro in the servo update routine, causing it to become unresponsive.

This bug has been present since we first released the Micro Maestro almost 10 years ago in November of 2009, but its effects tend to be subtle, and we only learned about it a few weeks ago when a customer brought it to our attention.

This bug does not affect the 12-channel, 18-channel, and 24-channel Mini Maestros, so there is no corresponding update for them. The latest Mini Maestro firmware version is still 1.03.

For information about how to upgrade your 6-channel Micro Maestro, see the “Upgrading Firmware” section of the Maestro user’s guide.