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Stepper motor driver's behavior while magic smoke came out

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sairfan1:
I'm setting up small CNC, my objective is to lean G Code commands and moving X, Y and Z axis

While just testing and driving motors some DRV8825 gave magic smoke and my arduino was also gone. I noticed there are other stepper drivers like A4988, TMC2209

I want to know which one is better, OR they are all same? any of these have any protection like in case of short circuit it keeps the higher voltage and arduino 5v separate?

Ian.M:
Dying gracefully is rarely a specified feature of *ANY* power interface/driver chip.  I thought I'd made that clear in your previous topic: https://www.eevblog.com/forum/beginners/stepper-driver-drv8825-gave-magic-smoke-what-could-be-the-reason/ but perhaps I need to go into more detail.   While portions of the silicon die are in the process of failing by melting or vaporizing,  transient voltages that may appear on supposedly logic level input pins are entirely unpredictable as they depend on things like how the meltdown propagates across the die and in high energy failures, which bond wires fuse first.  If the Gnd bond wire fails first the input pins may get directly connected to Vcc until the expanding metal and silicon vapors rupture the package, which may (or may not) break the connection.

If cascading damage from a power interface/driver chip blowout is unacceptable then control circuits must be protected against sustained direct connection to any voltage rail present outside the logic supply rails (Logic Vcc and Gnd).  This can be done in a number of ways, including series resistors + clamps on the logic side, or optoisolators, which should be regarded as sacrificial as the side connected to the power interface/driver chip is likely to get damaged in any high energy failure.

Doctorandus_P:
So now I see you are the same guy who keeps up blowing USB isolators by applying high voltages to their secondary side.

It probably is some kind of wiring error.

Another possibility is just a crappy 24V power supply.
When a coil of a stepper motor is turned off, then the current has to go somewhere, and it is usually redirected to the positive supply rails via diodes in the stepper motor drivers. As a result the 24V supply rails rises. This can be a serious problem, especially if you have big stepper motors and a lot of inertia behind them. Then the motors can act as dynamo's during deceleration and this can increase the power supply to beyond what the stepper motor drivers can handle and destroy them. Big electrolytic capacitors on the power supply rails reduce this issue, but sometimes even voltage clamps and bleed-off resistors are added to the power supply to prevent it from rising too much during such events.

jmelson:
I used to sell the 8825 drivers, now I am seling the 4988's, as their microstepping seems to work much better with some motors.  But, I don't know if one is more robust than the other.  You do need a large capacitor to remove spikes on the DC motor supply, close to the driver.
Jon

sairfan1:

--- Quote ---So now I see you are the same guy who keeps up blowing USB isolators by applying high voltages to their secondary side.
--- End quote ---
getting famous on the forum  ;D


--- Quote ---Big electrolytic capacitors on the power supply rails reduce this issue
--- End quote ---


--- Quote ---You do need a large capacitor to remove spikes on the DC motor supply
--- End quote ---

I'm using RAMPS board it has 35v capacitors near each driver, do you think its enough?
Thing that worries me is, I was not doing anything just turned on the power and its gone, before this everything was working all good, and i did not change anything to the related driver. I ordered new modules and its going to waste my about 25/30 days, I'm more towards learn how to minimize risk of such accidents.  If its something rare but happens then its ok, I'm worried what if new items comes in and I burn them again.








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