The 24V Step-Up/Step-Down Voltage Regulator S18V20F24 is the newest addition to our line of S18V20x step-up/step-down voltage regulators.

This 24 V fixed-voltage version is a minor modification of the 9 V to 30 V adjustable version we have been making for years. We can make custom-voltage versions of most of our regulators, and this particular unit was initially one of those customizations we routinely offer. However, since 24 V seems like it might be common enough to be interesting to other customers, we have made it a stock product. Since we assemble these at our Las Vegas, Nevada facility, we can often make simple customizations that only require component changes within a few days. Besides changing output voltages on regulators, these changes could include changing LED colors, omitting components such as pull-up or pull-down resistors, and substituting components with higher temperature ratings or better tolerances. (We offer more involved customizations that require modified board layouts or new firmware features, but those take longer and have higher up-front engineering costs.)

Pololu electronics manufacturing area with multiple pick and place lines.

For those of you interested in the details of the actual product, the S18V20F24 efficiently produces a fixed 24 V output from input voltages between 3 V and 30 V while allowing a typical output current of up to 2 A when the input voltage is close to the output voltage. Its ability to convert both higher and lower input voltages makes it useful for applications where the power supply voltage can vary greatly, as with batteries that start above but discharge below the regulated voltage. Other features include integrated reverse-voltage protection, over-current protection, over-temperature shutoff, and under-voltage lockout.

Typical efficiency of Pololu 24V step-up/step down voltage regulator S18V20F24.

Typical maximum output current of Pololu fixed voltage step-up/step-down voltage regulators (S18V20F5, S18V20F6, S18V20F9, S18V20F12, and S18V20F24).

Alternate versions of this regulator include a fixed 5 V, 6 V, 9 V, or 12 V output or an adjustable 4 V to 12 V or 9 V to 30 V output. Our full selection of regulators and power supplies can be found here.

Related products

	Pololu 5V Step-Up/Step-Down Voltage Regulator S18V20F5
	Pololu 6V Step-Up/Step-Down Voltage Regulator S18V20F6
	Pololu 9V Step-Up/Step-Down Voltage Regulator S18V20F9
	Pololu 12V Step-Up/Step-Down Voltage Regulator S18V20F12
	Pololu 24V Step-Up/Step-Down Voltage Regulator S18V20F24
	Pololu Adjustable 4-12V Step-Up/Step-Down Voltage Regulator S18V20ALV
	Pololu Adjustable 9-30V Step-Up/Step-Down Voltage Regulator S18V20AHV

Our rapidly growing selection of new QTR sensors now includes high-density (HD) versions with 13 and 25 channels, and medium-density (MD) versions with 7 and 13 channels. These QTR sensors are well suited for applications that require detection of changes in reflectivity. This change in reflectivity can be due to a color change at a fixed distance, such as when sensing a black line on a white background, as well as due to a change in the distance to or presence of an object in front of the sensor. Just like the 16-channel medium-density arrays we released in December, the 13-channel medium-density modules use PCBs specifically designed for an 8 mm pitch that allow separate control of the odd and even emitters, which gives you extra options for detecting light reflected at various angles. They have the same board dimensions (101 × 16.5 mm) and mounting hole locations as the high-density (4 mm pitch) 25-channel arrays, but the pinout is different.

Each of these is available with two sensor options—traditional QTR and high-performance, low-current QTRX—and with analog or digital (RC) outputs, making 16 new products in all. Check out the QTR reflectance sensor category to see our full selection of new-style QTRs with black PCBs, which now stands at 96 varieties, and don’t forget to use our QTR introductory promotion to get 50% off any of these new sensors! (Limited to the first 100 customers who use coupon code QTRINTRO, limit 3 per item per customer.)

Related products

	QTR-HD-25RC Reflectance Sensor Array: 25-Channel, 4mm Pitch, RC Output
	QTR-HD-25A Reflectance Sensor Array: 25-Channel, 4mm Pitch, Analog Output
	QTRX-HD-25RC Reflectance Sensor Array: 25-Channel, 4mm Pitch, RC Output, Low Current
	QTRX-HD-25A Reflectance Sensor Array: 25-Channel, 4mm Pitch, Analog Output, Low Current
	QTR-HD-13RC Reflectance Sensor Array: 13-Channel, 4mm Pitch, RC Output
	QTR-HD-13A Reflectance Sensor Array: 13-Channel, 4mm Pitch, Analog Output
	QTRX-HD-13RC Reflectance Sensor Array: 13-Channel, 4mm Pitch, RC Output, Low Current
	QTRX-HD-13A Reflectance Sensor Array: 13-Channel, 4mm Pitch, Analog Output, Low Current
	QTR-MD-13RC Reflectance Sensor Array: 13-Channel, 8mm Pitch, RC Output
	QTR-MD-13A Reflectance Sensor Array: 13-Channel, 8mm Pitch, Analog Output
	QTRX-MD-13RC Reflectance Sensor Array: 13-Channel, 8mm Pitch, RC Output, Low Current
	QTRX-MD-13A Reflectance Sensor Array: 13-Channel, 8mm Pitch, Analog Output, Low Current
	QTR-MD-07RC Reflectance Sensor Array: 7-Channel, 8mm Pitch, RC Output
	QTR-MD-07A Reflectance Sensor Array: 7-Channel, 8mm Pitch, Analog Output
	QTRX-MD-07RC Reflectance Sensor Array: 7-Channel, 8mm Pitch, RC Output, Low Current
	QTRX-MD-07A Reflectance Sensor Array: 7-Channel, 8mm Pitch, Analog Output, Low Current

I am excited to announce the release of the Tic T249 USB Multi-Interface Stepper Motor Controller, the fourth model in our line of Tic Stepper Motor Controllers. The Tic T249, which is based on the TB67S249FTG IC from Toshiba, features a broad 10 V to 47 V operating range and can deliver up to approximately 1.8 A per phase without a heat sink or forced air flow, making it our highest-power Tic yet. In addition to the array of high-level features offered by the other members of our Tic family, the Tic T249 offers access to several innovative features of the TB67S249FTG driver. Continued…

I am happy to announce our first new product of 2019, a carrier board for the STSPIN220 stepper motor driver, which operates all the way down to 1.8 V, making it our lowest-voltage stepper motor driver. And like its higher-voltage sibling, the STSPIN820 that we released a few months ago, it offers microstepping down to 1/256 steps. This new carrier board has the same 16-pin, 0.6″ × 0.8″ form factor as our other popular stepper motor drivers, and as with our STSPIN820 carrier, it inverts the enable input so that it has the more familiar functionality of those drivers (but be careful not to pop these into a 12 V or 24 V socket!).

By the way, keep in mind that you do not necessarily need a low-voltage stepper motor driver just because your stepper motor has a low rated voltage. The voltage rating is just the voltage at which your stepper motor will draw its rated current, and it’s really the current rating that you need to be careful about if you want to avoid damaging your stepper motor. All of our stepper motor drivers let you limit the maximum current, so as long as you set the limit below the rated current, you will be within spec for your motor, even if the voltage exceeds the rated voltage. In general, using a high supply voltage along with active current limiting allows for better performance, so the main reason for using a low-voltage stepper motor driver like the STSPIN220 is if your supply voltage is constrained to some low value by some other aspect of your system.

This new release brings our selection of stepper motor drivers in this compact form factor to eleven:

	A4988 (original)	A4988, Black Ed.	DRV8825	DRV8834	DRV8880	MP6500, Pot. CC	MP6500, Digital CC	TB67S279­FTG	TB67S249­FTG	STSPIN­820	STSPIN­220
Driver chip:	A4988		DRV8825	DRV8834	DRV8880	MP6500		TB67S279­FTG	TB67S249­FTG	STSPIN­820	STSPIN­220
Min operating voltage:	8 V		8.2 V	2.5 V	6.5 V	4.5 V		10 V	10 V	7 V	1.8 V
Max operating voltage:	35 V		45 V	10.8 V	45 V	35 V		47 V	47 V	45 V	10 V
Max continuous current per phase:(1)	1 A	1.2 A	1.5 A	1.5 A	1 A	1.5 A		1.1 A	1.6 A	0.9 A	1.1 A
Peak current per phase:(2)	2 A		2.2 A	2 A	1.6 A	2.5 A	2 A	2 A	4.5 A	1.5 A	1.3 A
Microstepping down to:	1/16		1/32	1/32	1/16	1/8		1/32	1/32	1/256	1/256
Board layer count:	2	4	4	4	4	4		4	4	4	4
Special features:			high current	low-voltage operation, high current	AutoTune, digital current reduction	high current	digital current control, high current	Auto Gain Control, ADMD, high max voltage	Auto Gain Control, ADMD, high max voltage, high current	128 and 256 microsteps, high max voltage	64, 128, and 256 microsteps, low-voltage operation
1-piece price:	$8.95	$9.95	$15.95	$9.95	$8.95	$9.95	$9.95	$11.75	$13.95	$18.95	$10.95
1 On Pololu carrier board, at room temperature, and without additional cooling. 2 Maximum theoretical current based on components on the board (additional cooling required).

Last year, we began offering introductory specials to celebrate each newly released product, and we are continuing with that this year: the first 100 customers that use coupon code STSPIN220INTRO can get up to five units at just $3.77 each.

Related products

	STSPIN220 Low-Voltage Stepper Motor Driver Carrier
	STSPIN220 Low-Voltage Stepper Motor Driver Carrier (Header Pins Soldered)

QTR-MD-16A Reflectance Sensor Array.

We now have 16-sensor, medium-density (8mm-pitch) versions of our new QTR reflectance sensor arrays. Like the versions already released, these new modules are available in analog and RC configurations and with two different sensor types, resulting in four new products in all:

• QTR-MD-16RC Reflectance Sensor Array
• QTR-MD-16A Reflectance Sensor Array
• QTRX-MD-16RC Reflectance Sensor Array
• QTRX-MD-16A Reflectance Sensor Array

Unlike the medium-density (MD) arrays we have released previously, which just use the high-density PCBs in partially populated configurations, these new 16-channel modules use PCBs specifically designed for an 8 mm pitch. As a result, these are the first MD versions that allow separate control of the odd and even emitters, which gives you extra options for detecting light reflected at various angles. They have the same board dimensions (125 × 16.5 mm) and mounting hole locations as the high-density (4mm-pitch) 31-channel arrays, but the pinout is different.

QTR-MD-16A Reflectance Sensor Array.

QTR-HD-31A Reflectance Sensor Array.

For more information on our new QTR sensor family, you can see some of our previous blog posts about the versions we have already released:

• New products: 1- and 31-channel QTR HD reflectance sensor arrays
• New products: more new QTR HD sensor arrays by student engineering interns
• New products: QTR HD sensor arrays by student engineering interns
• New product: high-density QTR reflectance sensor arrays

Don’t forget to get in on our QTR introductory promotion! Be one of the first 100 customers to use coupon code QTRINTRO and get any of these new sensors at half price! (Limit 3 per item per customer.)

Related products

	QTRX-MD-16RC Reflectance Sensor Array: 16-Channel, 8mm Pitch, RC Output, Low Current
	QTRX-MD-16A Reflectance Sensor Array: 16-Channel, 8mm Pitch, Analog Output, Low Current
	QTR-MD-16RC Reflectance Sensor Array: 16-Channel, 8mm Pitch, RC Output
	QTR-MD-16A Reflectance Sensor Array: 16-Channel, 8mm Pitch, Analog Output

We now have a 5-Channel Reflectance Sensor Array designed specifically for use with the Balboa 32U4 Balancing Robot. The array mounts to the Balboa 32U4 control board and provides an easy way to add line sensing to the Balboa (but following a line while balancing is actually kinda hard—and that part is up to you, should you accept the challenge).

The array features five IR emitter/phototransistor pairs with dimmable brightness control similar to our line of QTR reflectance sensors.

As with all of our new products this year, we are offering an introductory special. The sensor by itself is already inexpensive, so just discounting that did not seem exciting enough. To make it more celebratory, we decided to offer a special promotion for the whole Balboa package: you can get a Balboa 32U4 robot kit with motors, wheels, and the new 5-Channel Reflectance Sensor Array for just $79! To get the discounted price, add this special promotion product bundle and coupon code BALBOAREFLECT to your cart. Offer is limited to the first 100 customers, limit one per customer. If you already have a Balboa, or if you want different motors or wheels than what’s included in the bundle, you can use coupon code BALBOAREFLECT2 to save 35% (limit 2 per item).

Related products

	5-Channel Reflectance Sensor Array for Balboa 32U4 Balancing Robot
	Balboa 32U4 Balancing Robot Kit (No Motors or Wheels)
	Special Promotion: Balboa 32U4 Balancing Robot Kit with Gearmotors, Wheels, and Reflectance Sensor Array

We are excited to announce the newest additions to our selection of servos:

• FEETECH FS90-FB Micro Servo with Position Feedback
• FEETECH FS5103B-FB Standard Servo with Position Feedback

These specially modified versions of the standard FEETECH FS90 and FS5103B servos provide direct access to the feedback potentiometer through an extra fourth wire. Additionally, the FS90-FB has an extra long cable relative to the standard FS90 micro servo. The inclusion of a feedback wire allows you to monitor the servo’s position, which is especially useful for more complex robotic applications. 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. This feedback voltage varies linearly over the servo’s range of motion.

These servos are similar to those used in the Robot Arm Kit for Romi and Micro Gripper Kit and can be used as replacements for those servos.

These are just the start of our eventual selection of FEETECH servos with position feedback, so keep an eye on our blog and New Products category for more to come!

Related products

	FEETECH FS90-FB Micro Servo with Position Feedback
	FEETECH Standard Servo FS5103B-FB with Position Feedback
	FEETECH FS90 Micro Servo
	FEETECH Standard Servo FS5103B

We have yet another new stepper motor driver carrier in our popular 16-pin, 0.6″ × 0.8″ form factor, this time for STMicro’s STSPIN820, which offers 1/256 step microstepping! ST actually has their own similar evaluation board, the EVALSP820-XS, but the STSPIN820 chip has a non-inverted Enable input, which is inverted compared to most other stepper motor driver ICs out there, and they expose the pin that way on their version of the board. We have thoughtfully added a transistor-based inverter so that our board is more likely to work as a drop-in replacement (or upgrade!) for the stepper driver boards you already have. In our tests, the Pololu carrier supported a substantially higher maximum current than the ST eval board (around 900 mA compared to 720 mA, probably due to our board having four layers vs. two layers for the ST eval board), and as of this writing (27 November 2018), our board is also priced lower.

You can see the full schematic for all the details (this schematic is also available as a downloadable pdf (109k pdf)):

Schematic diagram of the STSPIN820 Stepper Motor Driver Carrier.

With our release earlier in November of compact carriers for Toshiba’s TB67S249FTG and TB67S279FTG stepper motor drivers, we now offer ten different stepper motor driver modules in this compact size:

	A4988 (original)	A4988, Black Ed.	DRV8825	DRV8834	DRV8880	MP6500, Pot. CC	MP6500, Digital CC	TB67S279­FTG	TB67S249­FTG	STSPIN­820
Driver chip:	A4988		DRV8825	DRV8834	DRV8880	MP6500		TB67S279­FTG	TB67S249­FTG	STSPIN­820
Min operating voltage:	8 V		8.2 V	2.5 V	6.5 V	4.5 V		10 V	10 V	7 V
Max operating voltage:	35 V		45 V	10.8 V	45 V	35 V		47 V	47 V	45 V
Max continuous current per phase:(1)	1 A	1.2 A	1.5 A	1.5 A	1 A	1.5 A		1.1 A	1.6 A	0.9 A
Peak current per phase:(2)	2 A		2.2 A	2 A	1.6 A	2.5 A	2 A	2 A	4.5 A	1.5 A
Microstepping down to:	1/16		1/32	1/32	1/16	1/8		1/32	1/32	1/256
Board layer count:	2	4	4	4	4	4		4	4	4
Special features:			high current	low-voltage operation, high current	AutoTune, digital current reduction	high current	digital current control, high current	Auto Gain Control, ADMD, high max voltage	Auto Gain Control, ADMD, high max voltage, high current	128 and 256 microsteps
1-piece price:	$8.95	$9.95	$15.95	$9.95	$8.95	$9.95	$9.95	$11.75	$13.95	$18.95
1 On Pololu carrier board, at room temperature, and without additional cooling. 2 Maximum theoretical current based on components on the board (additional cooling required).

As with all of our new products this year, we are offering an introductory special. The first 100 customers that use coupon code STSPIN820INTRO can get up to five units at just $5 each.

Related products

STSPIN820 Stepper Motor Driver Carrier

RoboClaw 2×60AHV, 60VDC Motor Controller.

We are excited to offer eight new powerful motor controllers from Basicmicro (formerly Ion Motion Control):

• RoboClaw 2x60AHV, 60VDC
• RoboClaw 2x160A, 60VDC
• MCP233 Dual 30A, 34VDC
• MCP236 Dual 30A, 60VDC
• MCP263 Dual 60A, 34VDC
• MCP266 Dual 60A, 60VDC
• MCP2163 Dual 160A, 34VDC
• MCP2166 Dual 160A, 60VDC

The two new RoboClaws bring our total selection of those to nine versions. Unlike the other RoboClaws, which have a maximum operating voltage of 34 V, these new RoboClaws and some of the new MCP controllers can work up to 60 V and deliver a continuous 60 A or 120 A per channel, making them the most powerful motor controllers we carry by far.

MCP233 Dual 30A, 34VDC Advanced Motor Controller.

MCP263 Dual 60A, 34VDC Advanced Motor Controller.

MCP2163 Dual 160A, 34VDC Advanced Motor Controller.

The six MCP products are from Basicmicro’s rugged new line of MCP Advanced Motor Controllers, which are optionally programmable via a built-in scripting language and support a variety of interfaces, including USB serial, TTL serial, RS-232 serial, CAN bus, RC hobby servo pulses, and analog voltages. Here is a summary of the key features of the MCP:

• Simple bidirectional control of two brushed DC motors
• 10–34 V or 10–60 V operating supply range, depending on controller model
• 30 A to 160 A maximum continuous current output, depending on controller model
• Channel bridging allows control of a single motor with double the current capability
• Automatic current limiting reduces duty cycle when temperature exceeds 85° C
• Six communication or control options:
  1. USB serial interface (virtual COM port)
  2. 3.3 V logic-level (TTL) serial interface for direct connection to microcontrollers or other embedded controllers
  3. RS-232 serial interface
  4. CAN bus interface supporting CANopen protocol as master or slave device
  5. Hobby radio control (RC) pulse width interface for direct connection to an RC receiver or RC servo controller
  6. Analog voltage (0 V to 5 V) interface for direct connection to potentiometers and analog joysticks
• Automatic control switching with user-defined priority settings
• I²C interface accessible by user script
• Up to 20 user-defined input pins for control, feedback, or scripting, depending on controller model
• All inputs are 15 V tolerant for interfacing to industrial devices such as PLCs
• Up to 8 user-defined open-drain output pins (40 V max) for driving auxiliary loads, depending on controller model
• Multiple feedback options for PID closed-loop control:
  • Speed or position control with quadrature encoders, up to 21 million encoder pulses per second
  • Position control with analog encoders or potentiometers
  • (Open-loop control with no feedback also available)
• Programmable with built-in user scripting language
• Screw terminals for quick connect/disconnect
• Configurable via USB connection and PC software
• Regenerative braking
• Tolerates high-speed direction changes
• 5 V BEC can power external logic
• Battery monitoring and under-voltage cutoff protects batteries from over-discharging
• Fully enclosed for protection
• Conduction plate for cooling on bottom of enclosure

Related products

	RoboClaw 2x60AHV, 60VDC Motor Controller (V6)
	RoboClaw 2x160A, 60VDC Motor Controller
	MCP233 Dual 30A, 34VDC Advanced Motor Controller
	MCP236 Dual 30A, 60VDC Advanced Motor Controller
	MCP263 Dual 60A, 34VDC Advanced Motor Controller
	MCP266 Dual 60A, 60VDC Advanced Motor Controller
	MCP2163 Dual 160A, 34VDC Advanced Motor Controller
	MCP2166 Dual 160A, 60VDC Advanced Motor Controller

Earlier this week, we released new compact carriers for Toshiba’s great stepper motor drivers, the TB67S249FTG and TB67S279FTG. We released larger carrier boards for those two chips in the summer, and those are still the version to get if you want to test all the features that those ICs offer. The new compact carriers are in our popular 16-pin, 0.6″ × 0.8″ form factor (which I originally designed for the Allegro A4983 back in 2009 when I was still routing most of our circuit boards), making it easy to use the new drivers on RAMPS-type 3D printer controllers that have the compatible sockets.

These Toshiba chips are massive, and you can see how much more space they take up on that common PCB size when compared to the original board (populated with the Allegro A4988 that replaced the A4983):

TB67S249FTG Stepper Motor Driver Compact Carrier (top view).

A4988 stepper motor driver carrier, top view (shown with original green 50 mΩ current sense resistors).

In addition to fitting the larger chip onto the same board space, we had to add some external inverters to make the enable and reset lines behave the same way as on the original modules (this schematic is also available as a downloadable pdf (141k pdf)).

Schematic diagram of the TB67S249FTG/TB67S279FTG Stepper Motor Driver Compact Carrier.

We also had to hardwire many of the options that the TB67Sx49FTG chips offer. In particular, we set the Active Gain Control (AGC) lower current limit to 60%. This innovative feature on the Toshiba stepper drivers allows the current through the stepper motor to be reduced based on what the motor actually needs, which allows for reduced unnecessary heat generation in the motor and higher peak power when you actually need it. I have heard (from Toshiba’s competitors, who also acknowledged that Toshiba is one of the few big semiconductor companies bringing real innovation to stepper motor drivers) of the AGC feature not working in some applications, but when it works, it’s quite amazing. We tried out the Toshiba TB67S249FTG drivers on a Tevo Tornado 3D printer that originally had Allegro A4988 drivers on an MKS GEN control board, and we could run at higher current and with 1/32 microstepping instead of the A4988’s 1/16 microstepping, which also gave a noticeable improvement in print quality.

The TB67S249FTG is now our highest-power option, and in addition to delivering a little bit more power than our previous leader, the TI DRV8825, the Toshiba driver seems to provide better current control with the relatively low inductance, low resistance coils often used on these low-end 3D printers. If you do not need that maximum current aspect, you can get all the other special features with the lower-power, lower-cost TB67S279FTG.

As with all of our new products this year, we are offering an introductory special. For these two new modules, we are offering 40% off for up to five units (per version!) to the first 100 customers that use coupon code TB67SCOMPACT. This means you can try out the top-of-the-line TB67S249FTG for less than $6.

Related products

	TB67S249FTG Stepper Motor Driver Compact Carrier
	TB67S279FTG Stepper Motor Driver Compact Carrier