TB6560 Stepper Driver Board

Over the past year I have invested some time and very little money in a new hobby, collecting 'essential' electronic items from China via ebay at the absolute minimum auction prices.
One of these was a TB6560 driver board identical to the one in the first link but at a somewhat lower price.

Using a surprisingly cheap laptop power supply rated at 19v and 3.2A I ran a number of bipolar steppers using an 08M Picaxe.
S: Pulsout 1,5: pause 1: goto s

The smallest motor is a surplus head positioning threaded rod motor.
15mm diameter 10.5mm long 15g 14 Ohms. Runs well at 0.3A.

Next is courtesy of Stan Swan who showed that they can be driven directly from Picaxe output pins. Thanks again Stan.
20mm diameter 14mm long 20g 115 Ohms. Runs well at 0.3A.

One of a collection of rescued printer steppers.
42mm diameter 15.5mm long 94g 12 Ohms. Runs well on 0.3A and 0.5A.

Hybrid from Arceurotrade.
57 X 57 X 76mm long 1.1Kg 4 Ohms 4.5v 2.5A/Phase 180N.cm. Runs well from 0.3A to 2A.

Hybrid from CNC4YOU.
60 X 60 X 88mm long 1.4Kg 2.6 Ohms 5.46v 2.1A/Phase 3.1N.m. Runs well from 0.5A to 2A.

Functionality is well illustrated in the first link, the second is for a UK seller with a link to a forum and a clear picture of possible connections.
I would point out that I use only the step input and a return to the Picaxe as the reverse and enable functions need only be connected when required.
Opto isolators on these functions mean that there need be no common ground connection between the Picaxe and the driver board.

There are 14 possible settings for the regulation of phase current from 0.3A to 3A irrespective of the nominal voltage and resistance of the motor. The inductance of the motor windings delay the build up of the current in the windings but the higher supply voltage can overcome this to some extent up to the point where current regulation circuit holds the current 'effectively' steady for the length of the motor step.

Microstepping at 2, 8 and 16 works well on all these motors and there is some evidence on the web that very high rates can be contraputical.

When powered and stationary between steps the motor presents only the resistance of the coils so the board cuts the current to a choice of 50% or 20% of the selected value. The faster a motor steps the less current it can draw allowing small motors to be powered at the 300mA setting with only 60mA while stationary.

All the motors run normally at different Decay settings, subjectively I sense that there is increased smoothness at the highest settings on the bigger motors but feel that testing would be needed for best results.

These boards have not had a good response on the web and granted the Datasheet states that the 5v to the logic circuit must be connected before power is applied to the motor. An onboard regulator supplies the logic, however the 10V to 24V specification for these boards is lower than the 40V VM A/B on the Datasheet.

Dave

http://www.ebay.co.uk/itm/TB6560-3A-Driver-Board-CNC-Router-Single-1-Axis-Controller-Stepper-Motor-Drivers-/350922320630?pt=UK_BOI_Industrial_Automation_Control_ET&hash=item51b499aaf6

http://www.ebay.co.uk/itm/TB6560-3A-Single-axis-Stepper-Motor-Driver-Controller-Board-/141106624015?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item20da9c360f

nice write up,

Would it be possible to to do some testing sending a PWM signal to the driver instead of of pulsout, the small amount if testing i did with me THB6406 showed a reduction in torque produced by the motor at half the max rate the driver could handle (200khz was max, motor would not rotate at that speed).

i would think the voltage restrictions on the board are alot lower than that of the actual IC due to keeping production costs down, however with that said you may well be able to push more voltage providing you keep the current down. While on the subject how did you fond micro stepping at different voltages, i found that unless i was at least double the motors rating torque output was low and the more easily stalled - my motor is rated for 44N,cm and with with 6v or more (motor rated for 2.8v, current being run at 7.2v) i find that thing near unstopable while trying to grip the plain shaft

At a glance, those two larger motors are way too big to be driving
with both the TB6560 driver board and Power supply shown.
e.g 2.5A/Phase = 5A
And there is a lot of difference between 12 Ohms and 2.6 Ohms.
As a ballpark example, think Amplifiers and Speakers 12 Ohm Load vs 2.6 Ohm load.
Melting silicon comes to mind.
One of these may be better >
https://www.google.com.au/search?q=5A+stepper+motor+driver&safe=off&source=lnms&tbm=isch&sa=X&ei=zHL4UvWKGIfwkgWL44GQDw&ved=0CAcQ_AUoAQ&biw=1140&bih=550#q=4.2+A+stepper+motor+driver&safe=off&tbm=isch

you will never get any where near 5amp, or for the matter i very much doubt you will get to 2.5A

the board i am currently using will peak at 4.5 amp per coil, but will deliver continuos 4A per coil. even with that said, the TB6560 is rated for 3.5A for the AHQ Variant (2.5A for the AFQ variant) per phase, providing that the data sheet is have is correct. Also while using a switching/ buck driver there is less current drawn by the entire system, providing you at least double the voltage requiremnt of the motor.

FYI the motor i running needs 1.68 amps per coil, i am running it at 2.5amp battery, battery life seems more than fine with limited testing i have done, doubling the current is needed

My intention had been to show that a chopper driver board gets more power from a given stepper and gives more control with less effort.
I wanted to demonstrate how easy it could be with the simplest code but have been told that I failed to make clear that my one line of text was the 'program' that I used to run the motors, so ~

Start:
pulsout 1,5 '..........output a 50 microsecond pulse on GPIO1 (pin6)
pause 1 '................create a delay of 1 millisecond.
goto Start

From this one might expect 1 pulse every millisecond but this is one of the few places that the timing overhead of the interpreter is important, the oscilloscope shows 1 pulse nearer to every 2 milliseconds.

Oracacle,
Thank you.

I have used PWM successfully for steppers with the help of the Wizard but the reduction in torque at speed that you see with your motor is a feature of stepper motors.
The graph shows torque against speed for a generic stepper rated at 3.7V running at up to 75 volts and is taken from page 10 of the link.
This together with your own findings would suggest that a further increase in voltage may well improve performance.

At the same speed without microstepping and set at 2 amps the current of the CNC4YOU motor was 0.29A in one phase.
Microstepping at 16 the current was 0.67A .



Michael,
On the same page of that link it also expands on the following statement.

[ Typically a power supply capable of delivering ½ or more of the peak phase current should be sufficient. ]

Dave

http://www.ams2000.com/pdf/step101.pdf