Improving the most versatile H Bridge you will ever find

Download AE-CNCBridge data sheet
Download AE-CNCBridge Schematic
Download AE-CNCBridge BOM


When I designed the MonstroStep (not yet released) bipolar stepper driver capable of driving up to 5A stepper motors I quickly set to build my first CNC machine. 5A are more than plenty to drive most behemoths so I was completely excited about this prospect!

Building a CNC machine today is not too hard. There is a gazillion places on the web detailing what you need to do so I will not bore you with details. All you need is a parallel port interface card to get your control signals from a program such as MACH3 or EMC and walas! Your stepper motors run to the orchestration of G Code. Hopefully to cut whatever design you need your CNC router, lathe, plasma cutter, foam cutter, etc to build.

Unfortunately, there was a problem... The available parallel port cars did not allow for my 3.3V tolerant logic a clean interface with the PC parallel port. So I set to build my own board and I am happy to report the AE-CNCBridge is a gorgeous creation you can now have for free!

The idea behind the CNCBridge is to connect your stepper drivers to the PC parallel port through a level shifter buffer which allows practically any voltage combination you can think of. 3.3V to 5V, 5V to 3.3V, 5V to 5V and 3.3V to 3.3V are all supported. Granted that our PC’s are all 5V, so chances are this will be your starting point. Jumpers select which voltage you want to use for the inputs and the outputs.

An USB connector gives you 5V from the computer and regulates down to 3.3V so an external power supply is not needed as with other cards. The level shifter chips are socketed so in case of an accident, you can exchange them for fresh units. At the same time, this protects the PC parallel port.

There is access for four stepper motors, four home switches and the emergency switch. Each stepper connection offers the typical ENABLE / DIRECTION / STEP signals along with a power supply rail that can be selected between 3.3V and 5V to ensure compatibility with your own stepper driver boards. Home switches are pre configured to 5V rail.

Using this board can not be easier. Use our resources to build your own or modify your own design according to what you define best.

This board will be available for purchasing by the month of March 2011.

Bare Board:



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