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I am referring Stepper Motor driver IC DRV8824 and TEA3718.

I want to increase speed of rotation and as per datasheet of DRV8824, rising edge on step pin causes the indexer to move one step.

Does it increases speed of stepper motor? TEA3718 doesn't have step pin, so can I say we can't increase motor speed in TEA3718?

Please someone explain. Thanks.

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2 Answers 2

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Yes, higher frequencies on the step pin for the DRV8824 will increase the speed of the motor by moving more steps per unit time.

With the TEA3718, the design topology is different. It's basically an H-bridge with some current alarms and variable drive current settings (INA and INB). Take a good look at the datasheet, particularly the typical application schematic (where you see that two of these ICs are required for a 4-wire stepper). Also, take a look at the Principal Operating Sequence to see how INA and INB can be used to implement half-stepping. You can absolutely vary the speed by varying the frequency of the waveform applied to the phase input of the TEA3718, but you will need to control this synchronously with another signal for the other phase.

Effectively, the TEA3718 is a bit more general purpose, and could easily be used to drive more generic loads (brushed DC motors, for example). The DRV8824 is more of an application specific IC.

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  • \$\begingroup\$ Thanks for your reply. For half stepping and full stepping, speed is reduced. So can I say, full stepping is for highest speed? \$\endgroup\$ May 26, 2016 at 12:22
  • \$\begingroup\$ Not if you compensate by increasing the drive frequency. But the two signals are not really comparable - the step input is one-pulse-per-step - the phase input is half of a quadrature phase locked pair. You might want to look up how to drive stepper motors and look at the actual drive waveforms for the coils. \$\endgroup\$
    – stefandz
    May 26, 2016 at 12:25
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Your question is like asking how fast do the gears switch in an automatic transmission car verses a manual transmission car.

The DRV8824 is all automatic. The TI.COM chip is designed to take care of almost everything. Including micro-stepping.

The TEA3718 is mostly manual. The STMicroelectronics.com chip needs all kinds of processor support. Not only that, it looks like you need 2 TEA3718 chips to do the work of 1 DRV8824.

There are likely advantages for either choice: The DRV8824 needs less support and might be better for novice users. The TEA3718 is more flexible and may be better for experienced users.

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