Tiny Controls · Own design
Tstep-168X Stepper Driver
Two-phase stepper drive for 24-160 V DC or 18-110 V AC supplies, with output current jumper-selectable from 1.2 A to 8.0 A.
Overview
The Tstep-168X is the high-voltage member of the Tstep-X stepper drive range, intended for larger machines where a 24 V or 48 V supply leaves the motor short of headroom.
A stepper motor's usable torque falls away as step rate rises, because the winding inductance limits how quickly current can be driven into it. Raising the supply voltage is the direct remedy, and at up to 160 V DC the 168X keeps current rising fast enough to hold torque well into the higher speed range. It accepts an AC supply of 18-110 V as an alternative, so it can be fed straight from a transformer without a separate rectifier stage.
Output current is set by jumper anywhere from 1.2 A to 8.0 A, covering NEMA 23 through to larger NEMA 34 motors. Microstepping is selectable across seven settings - 4, 5, 8, 10, 16, 20 and 32 - so resolution can be matched to the controller's step rate rather than fixed at the highest value.
The STEP and DIR inputs are optically isolated, which keeps controller ground out of the motor power loop; that isolation is what stops a noisy spindle drive from injecting false steps. Idle current reduction drops the standing current when the axis is stationary, and short-circuit protection covers a shorted or mis-wired motor lead.
Designed and built by Tiny Controls in India, and repairable for the life of the machine.
Specifications
| Supply voltage | 24 - 160 V DC \ 18 - 110 V AC |
|---|---|
| Output current | 1.2 - 8.0 A |
| Microstepping | 4, 5, 8, 10, 16, 20, 32 |
| Current setting | DIP switch (S2-S5) |
| Idle current reduction | Yes |
| Short-circuit protection | Yes |
| STEP / DIR inputs | High Speed Optically Isolated |
Questions
Which motors does the Tstep-168X suit?
Motors drawing between 1.2 A and 8.0 A per phase, which covers NEMA 23 through larger NEMA 34 frames. Set the drive current to the motor's rated phase current, not above it.
Why choose the 168X over the 117X or 087X?
Supply voltage. The 168X accepts up to 160 V DC against 110 V and 80 V for the other two, and higher voltage is what preserves torque at higher step rates. If your axes run slowly, a lower-voltage drive is the cheaper choice.
Can it run from an AC transformer directly?
Yes. It accepts 18-110 V AC as well as 24-160 V DC, so a transformer secondary can feed it without a separate rectifier and filter stage.
What does idle current reduction do?
It lowers the standing current when the axis is not moving, which reduces heat in both the motor and the drive. Holding torque falls while idle, so it is not suitable where a stationary axis must resist a large load.