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S109 High Current Drivers

Khalid Baheyeldin
 

There are new high current stepper drivers providing up to 4A available from China.

They are the S109, based on the Toshiba TB67S109 chipset. The cost is ~ $8.30 CAD on eBay.

They are Pololu compatible, and work the same as the A4988, except that they provide up to 1/32 steps.

George Cushing
 

On Sat, Nov 17, 2018 at 11:40 AM, Khalid Baheyeldin wrote:

They are the S109, based on the Toshiba TB67S109 chipset. The cost is ~ $8.30 CAD on eBay.
Nice find! With a little broader search these came up 3D Printer Stepstick S109 Stepper Motor Driver Compatible With 57 Stepper Motor at $4.34 U.S.
https://www.ebay.com/itm/3D-Printer-Stepstick-S109-Stepper-Motor-Driver-Compatible-With-57-Stepper-Motor/253950525883?hash=item3b20a181bb:g:u4gAAOSwGsJb0pME:rk:18:pf:0

Rick Foust
 

Ordered 3 at $4.39 ea. 

Khalid Baheyeldin
 

Very good price.

Those will only be needed if one has high current motors that are beyond the 'usual' drivers.

As a result, OnStep can be used on bigger mounts that carry more load, without exotic wiring.

But please read the documentation, specially about heat dissipation and cooling ...

George Cushing
 

I have an 1987 Celestron Compustar 14 mount That in the day required a 15 amp power supply. It used two Vextra steppers rated at three amps. These drivers will let me test OnStep with the mount with little fabrication. If all works out I can experiment with lower current steppers and will only have to swap out the drivers.

Here's the original stepper driver based on TIPs. It was in a fan cooled box about 18 by 6 by 5".

Rick Foust
 

I received the S109 drivers today and had a chance to bench test them.  I tested them with my MKS GEN L board, at 24V, and with 24HS39-3008D motors (566oz.in, 8 wire connected in bipolar series, rated at 2.12 A, 12mH)  Here are my initial thoughts.

  1. No complaints regarding the manufacturing quality.
  2. The pin functions are not marked on the board.  The pin out diagram is available at  https://wiki.fysetc.com/S109_V1.1/
  3. The S109 heat sinks are half again wider and nearly three times taller than those supplied with A4988s.  I don't have room in my case to accommodate the height. 
  4. The S109 heat sinks cover up the pins.  The heat sink is rebated so as to not contact the pins, but it comes close.  The heat sinks are anodized, and so they are not electrically conductive on the surface (yes, I checked), but still, caution is advised.
  5. At 1/16 and 1/32, the S109 had the same noise level as the A4988s that I have been running.  They also have rhythm, similar to the A4988, but without the quick pause at the end of each cycle (200 steps). The S109 is more of a steady rmm, rmm, rmm vs the A4988 rmm pause, rmm pause, rmm pause.  If I listened carefully to the motor while being driven by the S109, I could hear a quick hiccup at random intervals of several cycles.  I did not hear this with the A4988.
  6. I have been cooling the A4988s at 1.3A with a 30mm 24V fan (necessary).  I tested the S109s up to 3.5A and they reached trip temp in a couple of minutes without fan cooling, but would easily handle it with fan cooling.  No fan was needed for 2A with the big heat sinks in the open air.  Enclosed in a case might be different.
  7. The S109 at 2A and with a little A4988 heat sink runs about 120F with a fan. 
  8. I like the S109 drivers and will be switching to them.  I will need to sand down the heat sink height to fit in my case, and fan cool them. 

Khalid Baheyeldin
 

Rick,

Thank you for a detailed and comprehensive review.

This is the kind of feedback that users can provide to help the project and the community as a whole.

Rick Foust
 

One of the S109 drivers failed.  See pics.  Some kind of grunge appears to have shorted it out.  It was all over the top of the driver, including under the heat sink and around the chip pins.  There was none on the underside of the S109 or on any other components or the case.  There are no signs of overheating or water intrusion.  The adjacent S109 driver looks like new.  The grunge cleaned off easily with water, but the driver was still dead.  I replaced it with another S109 and everything is back to normal. 

Roaster
 

Bat guano
 

From: Rick Foust
Sent: Saturday, December 29, 2018 1:44 AM
To: onstep@groups.io
Subject: Re: [onstep] S109 High Current Drivers
 
One of the S109 drivers failed.  See pics.  Some kind of grunge appears to have shorted it out.  It was all over the top of the driver, including under the heat sink and around the chip pins.  There was none on the underside of the S109 or on any other components or the case.  There are no signs of overheating or water intrusion.  The adjacent S109 driver looks like new.  The grunge cleaned off easily with water, but the driver was still dead.  I replaced it with another S109 and everything is back to normal. 

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