The first thing to understand with the comparison between a stepper motor driver and a stepper motor controller is that the terms are used rather interchangeably despite often being strictly incorrect.
As happens within many walks of life it is often quicker to refer to something as a ‘driver’ or ‘controller’ rather than a ‘combined stepper motor controller and driver’. (We are ourselves guilty of doing the same thing on this website for the sake of trying to make articles and descriptions easier to read).
A stepper motor driver is an electronic component which can convert an input signal of some kind into movement of the stepper motor without itself being able to issue instructions (or control) the stepper motor.
It is often useful to consider the driver as a ‘translator’ between input signals and the physical movement of the stepper motor.
In some cases stepper motor drivers may be designed specifically to work with a set communication protocol such as analogue or CANbus but the broad principle is simple – they do not have any ability to control the motor themselves except where they are given control instructions from a computer, PLC or other control device.
In contrast to this a stepper motor controller such as the ZD Series Stepper Motor Controllers can actively control and drive the motor itself. Strictly speaking such units should be referred to as a stepper motor driver and controller but it is perhaps understandable why people frequently shorten this down to stepper motor controller for ease of use.
A good visual example of this is probably the ZDLCD Series Stepper Motor Controllers. A stepper motor controller such as the ZD10LCD can quite clearly be seen to be both driving and controlling the stepper motor from the same unit.
The person using the controller puts in the instructions they need and the controller part of the unit then issues instructions to the driver part of the unit which converts the instructions into the physical sequences that the motor needs in order to turn.
In simple terms the most important thing to understand is what you need for your project to work well and whether or not this is a stepper motor controller or driver.
If you have any questions about this you can always contact us to talk to one of our engineers or alternatively review some of our similar questions in the FAQs section.