L6470 vs L6472

ppostig · ‎2013-10-02

Posted on October 02, 2013 at 17:40

Hello

I understand:

6470 uses voltage mode drive/bemf compensation

6472 uses current mode drive/adaptive decay comp compensation

If my uStep requirements are 1/16. What other parameters should I consider for my decision to choose one IC over the other.

thanks

#l6470-l6472

Enrico Poli · ‎2013-10-07

Posted on October 07, 2013 at 10:45

Hi,

The L6470 uses an open-loop approach. Thanks to the voltage mode driving it performs extremely smooth movements, but the application and motor characteristics must be well known in order to define the algorithm setup. The voltage mode is not suitable for full-step operation.

The L6472 implements a ''classic'' closed loop approach adding many extra features which help reducing current ripple. This method is more robust to the variation of the motor characteristics (same setup is good for a wide range of motors). It perfectly works in full-step.

In conclusion, if you are looking for extreme smoothness the voltage mode driving is a must (L6470). The advanced current mode (L6472) fits all other applications, but the mechanincal noise is higher (and it is not only a microstepping matter).

Regards

Enrico

ppostig · ‎2013-10-14

Posted on October 14, 2013 at 15:50

After a bit of characterization and tuning I found the 6470 smoother / quieter in operation over the 6472. The 6470 is more susceptible to resonant stalling over the 6472 in my application.

I found observing current waveforms and following AN4144 necessary when setting up the 6470.

Running in continues microstepping mode works best for my application

Why would a user need/wish to switch to full step using: â€˜FS_SPDâ€™ ?

Thanks again for your support

Enrico Poli · ‎2013-10-21

Posted on October 21, 2013 at 10:46

Glad to know that you found helpful our technical documentation.

The automatic full-step switch can be useful when the stepper motor is running at very high speed. In this case the full step driving can give to the motor a small extra torque.

However this feature is more interesting when the current control driving is used.

Regards

Enrico