TLA Microsystems (TLA_TOP.GIF-23k)

June 2017 - A distributor has recently informed customers that the Little Step-U (Parallax #27938) had been made obsolete. While it appears that they will no longer be selling it, we have a number of OEM customers using it and it will continue to be available directly from TLA Microsystems. There is no intention or expectation of discontinuing manufacture of the Little Step-U. However, because there has been a rush of direct orders following the notice, stock levels have suffered. We are working to remedy that and to provide an online purchase facility. We apologise for any inconvenience.


Little Step-U
Unipolar Stepper Motor Controller

Little Step-U (Motor2.JPG-13k)


The Little Step-U is a complete stepper motor control solution in the form of a 1" x 2" PCB. A single TTL serial connection is sufficient to control a 30V/3A unipolar motor up 5000 steps/second in a set and forget fashion. Commands instruct the motor to move to an absolute position, a relative position, until an input is activated or return to one of two previously marked positions. An inbuilt linear ramp function allows the motor to be accelerated and decelerated over a defined period. Other options are to drive the motor in full, half and wave drive modes, stop with windings on or off or to act as a simple translator/drive with step and direction inputs.
  • Unipolar motors to 35V, 3.0A
  • Full step, half step and wave drive modes
  • 1-5,000 steps per second
  • Inbuilt speed ramp (0.1-20.0 seconds)
  • Simple serial commands (TTL interface)
  • Separate power input for motor and logic
  • Suitable for direct and L/R operation in all modes
  • On board clamping diodes
  • Current position register (+/-100,000,000)
  • Zero position and user marker registers
  • Absolute & Relative movement commands
  • Busy output
  • Two inputs suitable for optical stops
  • Slave mode using inputs for STEP & DIR
  • Stop with motor coils on or off


Little Step-U (LSU.JPG-18k)


Command summary and pinout

Full Little Step-U datasheet (54k)

How to buy one


ph:  +64 9 820-2221           fax: +64 9 820-1929
PO Box 15-680, New Lynn, Auckland, New Zealand