This breakout board makes it easy to use Toshiba’s TB67S249FTG/ TB67S279FTG microstepping bipolar stepper motor driver, which features adjustable current limiting and seven microstep resolutions (down to 1/32-step). In addition, it dynamically selects an optimal decay mode by monitoring the actual motor current, and it can automatically reduce the driving current below the full amount when the motor is lightly loaded to minimize power and heat. The TB67S249FTG has a wide operating voltage range of 10 V to 47 V and can deliver approximately 1.7 A/ 1.2 A respectively per phase continuously without a heat sink or forced air flow (up to 4.5 A peak). It features built-in protection against under-voltage, over-current, and over-temperature conditions; our carrier board also adds reverse-voltage protection (up to 40 V).

This product is a carrier board or breakout board for Toshiba’s TB67S2x9FTG family of stepper motor drivers; we therefore recommend careful reading of the corresponding driver’s datasheet before using this product. This stepper motor driver lets you control one bipolar stepper motor and is available in two different versions: the TB67S249FTG can deliver about 1.7 A per phase continuously (4.5 A peak), and the TB67S279FTG can deliver about 1.2 A per phase continuously (2 A peak). (See the Power Dissipation Considerations section below for more information.)

The two versions of this stepper driver carrier look very similar, so you should consider adding your own distinguishing marks or labels if you will be working simultaneously with multiple versions. A white box is provided on the bottom silkscreen of the board to make labeling easier. This product page applies to both versions of the TB67S2x9FTG carrier.

Here are some of the board’s key features:

Simple step and direction control interface

Seven different step modes: full-step, non-circular half-step, circular half-step, 1/4-step, 1/8-step, 1/16-step, and 1/32-step

Adjustable current control lets you set the maximum current output with a potentiometer, which lets you use voltages above your stepper motor’s rated voltage to achieve higher step rates

Advanced Dynamic Mixed Decay (ADMD) dynamically switches between slow and fast decay modes by monitoring the state of current decay (not according to fixed timing)

Configurable Active Gain Control (AGC) automatically reduces drive current to minimize power consumption and heat generation when maximum torque is not needed

Motor supply voltage: 10 V to 47 V

Maximum continuous current per phase without additional cooling:

TB67S249FTG: 1.7 A (4.5 A peak)

TB67S279FTG: 1.2 A (2 A peak)

Built-in regulator (no external logic voltage supply needed)

Can interface directly with 3.3 V and 5 V systems

Under-voltage lockout and protection against over-current/short-circuit and over-temperature

Open-load detection

Active-low error outputs indicate over-current, over-temperature, or open-load condition

Carrier board adds reverse-voltage protection up to 40 V

Compact size (1.0″ × 1.4″)

Exposed solderable ground pad below the driver IC on the bottom of the PCB

Details for item

This version uses a TB67S249FTG/ TB67S279FTG driver and can deliver approximately 1.7 A/ 1.2 A respectively per phase continuously without a heat sink or forced air flow (up to 4.5 A peak). It can be distinguished by the marking “S249FTG” or “S279FTG”on the driver IC.

For more information about this driver, please read the

TB67S249FTG datasheet (533k pdf) and

TB67S279FTG datasheet (536k pdf)

Included hardware

This product ships with all surface-mount components—including the TB67S2x9FTG driver IC—installed as shown in the product picture. However, soldering is required for assembly of the included through-hole parts: two 1×15-pin breakaway 0.1″ male headers and three 2-pin, 3.5 mm terminal blocks (for board power and motor outputs).

The 0.1″ male header can be broken or cut into smaller pieces as desired and soldered into the smaller through-holes. These headers are compatible with solderless breadboards, 0.1″ female connectors, and our premium and pre-crimped jumper wires. The terminal blocks can be soldered into the larger holes to allow for convenient temporary connections of unterminated power and stepper motor wires. You can also solder your motor leads and other connections directly to the board for the most compact installation.

Using the driver

Power connections

The driver requires a motor supply voltage of 10 V to 47 V to be connected across VMOT and GND. This supply should be capable of delivering the expected stepper motor current.

A 5 V output from the TB67S2x9FTG’s internal regulator is made available on the VCC pin. This output can supply up to 5 mA to external loads.

Motor connections

Four, six, and eight-wire stepper motors can be driven by the TB67S2x9FTG if they are properly connected; a FAQ answer explains the proper wirings in detail.

Warning: Connecting or disconnecting a stepper motor while the driver is powered can destroy the driver. (More generally, rewiring anything while it is powered is asking for trouble.)

Pinout

TB67S2x9FTG Stepper Motor Driver Carrier, top view with labeled pinout.

PIN	Default Value	Description
VIN		10 V to 47 V board power supply connection (reverse-protected up to 40 V).
GND		Ground connection points for the motor power supply and control ground reference. The control source and the motor driver must share a common ground.
VM		This pin gives access to the motor power supply after the reverse-voltage protection MOSFET (see the board schematic below). It can be used to supply reverse-protected power to other components in the system. It is generally intended as an output, but it can also be used to supply board power.
A+		Motor A output: “positive” end of phase A coil.
A−		Motor output: “negative” end of phase A coil.
B+		Motor output: “positive” end of phase B coil.
B−		Motor output: “negative” end of phase B coil.
VCC		Regulated 5 V output: this pin gives access to the voltage from the internal regulator of the TB67S2x9FTG. The regulator can only provide a few milliamps, so the VCC output should only be used for logic inputs on the board (such as the neighboring DMODE pins), not for powering external devices.
VREFA, VREFB		Voltage reference pins for setting the current limit. By default, these pins are connected to the potentiometer and to each other so that the current limit is the same on both channels, but you can cut the trace between them to set the current limit for each motor channel separately.
DMODE0, DMODE1, DMODE2	LOW	Step resolution selection pins. These pins are all pulled low by default, putting the driver into a low-power standby mode and disabling the outputs; at least one DMODE pin must be driven high to set the step resolution and and allow the driver to operate.
CW/CCW (DIR)	LOW	Input that determines the direction of rotation.
CLK (STEP)	LOW	A rising edge on this input causes the driver to advance the motor by one step or microstep (moving the coil currents one step up or down in the translator table).
ENABLE	LOW	Enable input. By default, the driver pulls this pin low, disabling the motor outputs; it must be driven high to enable the driver.
RESET	LOW	Reset input: driving this pin high resets the driver’s internal electrical angle (the state in the translator table that it is outputting).
MO		This open-drain output is low when the driver’s internal electrical angle is at its initial value (the value after reset); otherwise, the board pulls it up to VCC.
LO1, LO2	HIGH	Error outputs: these pins drive low to indicate that an error condition has occurred; otherwise, the board pulls them up to VCC. The specific error can be determined by the state of both error pins.
AGC0, AGC1	HIGH	These inputs determine whether Active Gain Control (AGC) is enabled. AGC0 should not be changed while the driver is operating. See the datasheet and the Active Gain Control section below for details about the AGC feature.
CLIM0, CLIM1	HIGH, 100 kΩ pull-up	These inputs set the bottom (minimum) current limit when AGC is active. CLIM1 is a four-state input.
FLIM	100 kΩ pull-up	This four-state input sets the bottom frequency limit (minimum step rate) for AGC to be active.
BOOST	100 kΩ pull-up	This four-state input determines how quickly the motor current is boosted back to the normal limit after the driver detects increased load torque with AGC active.
LTH	100 kΩ pull-down	This input controls the AGC detection threshold (torque detection sensitivity).