Data Sheet

continuous current rating whenever you move the motor, and reducing it while the motor

is holding position, thus maintaining a low average current.) If the motor’s rated current is

substantially more than the Tic’s current, then it is possible that the Tic will not be able to

move the motor at all.

5. We generally recommend you choose a power supply with a current limit that is at least at

least twice the current limit you are planning to use on the Tic as that amount of current

should always be safely beyond what the Tic will draw. The current limit you configure on the

Tic should generally not exceed the stepper motor’s rated current and should not exceed the

continuous current per phase of the Tic. So if you take the smaller of those two currents, and

then multiply that current by two, and get a power supply that can provide at least the much

current, you can be sure that the power supply’s current will not be the limiting factor in your

application. However, please note that you can typically get by with less power supply current

than this, especially if your supply voltage is higher than the rated voltage of your stepper

motor. In this situation, the Tic’s current control acts as a step-down converter, meaning that

a small amount of current from the power supply at a higher voltage can generate a larger

amount of current going through the coils at a lower voltage. Also, the Tic never actually

drives both coils at the configured current limit at the same time. The total current going

through the coils is maximized in the four full-step positions, where the Tic will be sending

71% of the current limit through each coil, for a total current of 142% of the current limit. If

you want to know the maximum current draw from your power supply, you can measure this

with a multimeter while the stepper motor is energized in full-step mode and not stepping. If

your system draws too much current, your power supply might shut down, overheat, produce

a lower voltage, and/or be damaged.

It is worth noting again that since the Tic actively limits current through the motor coils,

you can safely use power supplies with voltages above the rated voltage of the stepper

motor as long as you set the current limit to not exceed the stepper motor’s rated current.

This means that the Tic T825 can be used with stepper motors that have rated voltages

below 8.5 V.

4.2. Connecting the stepper motor and power supply

The information in this section can help you connect your stepper motor and power supply to the Tic.

To avoid damage or injury, please read these safety warnings carefully:

4. Setting up the controller Page 21 of 150