RAMPS driver signal strength - Four motor z-axis

I've built a machine which uses 4 motors in the z-axis (picture attached). All the units have been tested individually using the A4988, which is slightly under powered.

I've ordered 9 of the TB6600 stepper drivers, which are inexpensive and look to be easy to wire and have a large heat sink built into them.

In the TB6600 data sheet, it rates the logic signal current as being 8 - 15mA maximum.

Can the RAMPS power 4 of these at once? That would be 32 - 60mA.

I notice the A4988 only requires 20 micro amps, 0.02mA.

I suspect it's a No-Go.

Is it possible to put some kind of an amplifier between the RAMPS board and the steppers?

It would be nice to have a way to run any machine of any size with a RAMPS.

Thank you very much, and I hope this topic hasn't been covered. I didn't see it in a quick search.

you may want to look at these "board Adapter Module External High Power Switching Module for Microstep Driver with 3D Printer"
[www.aliexpress.com]

I took a quick look around for more info, but there isn't much beyond the hookup guide.

It looks as if it uses the power from the RAMPS Vmot to amplify the signal.

It also looks as if it requires 24V, so I guess I'd be flipping that pin up, as I did with the A4988, to save soldering on the RAMPS.

Thank you very much. It looks like a very cost effective way of expanding RAMPS' capabilities.

I've attached the hookup guide image for the module. The switching module is on the right hand side, one's choice of stepper driver in the center, labeled as "High Power Module".

Edited 1 time(s). Last edit at 02/27/2022 10:36AM by kingopayne.

Good news!

I found the RAMPS 1.4 board has enough stepper driver signal to power four of the TB6600 steppers on one axis (z).

Unfortunately, the TB6600 drivers, which have an excellent layout (huge heat sink, and dipswitches and a table for setting stepper resolution and amperage) seem to be "fake". Looking online, people are writing that if it has 1/32 stepping, it's not a TB6600, but actually a TB67S109AFTG.

They work, but I'm still having trouble figuring out how to set the dipswitches for stepper resolution and amperage, as they seem to be upside down (maybe the stepper resolution switches aren't and the amperage switches are).

It's confusing, but I've got it working. It's possible the original design for the TB6600 enclosure was kept, dipswitches included, and the other Toshiba driver chip installed, which might explain why the dipswitches are so confusing to set up.

The LERGE External Switching Module don't seem to work for this application, so I've had to wire the drivers directly to the RAMPS 1.4 board STEP/DIR sockets. I couldn't find much information on the LERGE External Switching Modules, so am unsure as to whether they actually plug into an A4988 socket, or are made for a LERGE motherboard.

I also should note that the image I attached for the LERGE External Switching Module showed 24V, but the one I recieved had 5V printed on it.

Edited 1 time(s). Last edit at 03/20/2022 10:47AM by kingopayne.

The worst case logic input on the TB6600 is the TQ pin, which has an absolute maximum current of 105 microamps (0.000105 amps, or 0.105 milliamps to drive it to an acceptable logic level. All of the other logic pins are even less.

The 8-15 mA you refer to is what the pin protection circuit, internal to the chip, can tolerate, NOT what the pin needs to be properly driven. Any microprocessor can drive a TB6600 properly.