Modern replacement for LM628/629? Servo motor control

[Photon939]

I've been looking into the fact that small DC brushmotor servo drivers are not an easy item to find at reasonable prices.  The application I have in mind is CNC for stuff like 3d printers and laser cutters.  Is there a modern equivalent for the LM629 precision motion controller?
https://www.mouser.com/ProductDetail/Texas-Instruments/LM629M-6-NOPB?qs=sGAEpiMZZMvu8NZDyZ4K0Qh6JMP%252bT6Sa
I'm also open to the possibility of doing brushless motors as well.

I'm looking for drivers that integrate with incremental shaft encoders.

Thanks in advance for any suggestions.

[Kjelt]

I was wondering the same thing, my guess is that some things have changed since late 90s when the lm628/629 came out:

- cheap steppermotors replaced the brushed dc motors, also then no real need for encoders unless you have heavy usage such as cnc milling where you might loose steps.
- microcontrollers have become so cheap and powerfull that semiconductor manufacturers don't see a market anymore. A stm8 for $2 should be able to handle this esp. Dedicated to a single motor and encoder as the lm 62x's do

[danadak]

PSOC Motor Control -


http://www.cypress.com/applications/automotive-solutions/motor-control

Onboard DAC, ARM Core, A/D, Digital Filter + a whole lot more....


Regards, Dana.

[Kjelt]

PSOC Motor Control -
http://www.cypress.com/applications/automotive-solutions/motor-control
Onboard DAC, ARM Core, A/D, Digital Filter + a whole lot more...
Regards, Dana.

I don't see the feedback loop (quadrature decoder) which is what makes a motor a servo.

[perdrix]

You may wish to take a look at Microchip AN532 which describes a servo motor control system using a PIC17C42 and a PLD.

This was used very successfully as the basis of the dual servo motor controller in the Losmandy Gemini-1 telescope control system.

The 17C42 is now somewhat dated, but the concepts and the code are still valid and it could readily be ported to a newer PIC (beware clock rate differences).

HtH
David Partridge

[danadak]

There is a posted project here, if you have loaded Creator on you
PC.


http://www.cypress.com/forum/psoc-3-known-problems-and-solutions/servo-motor-interface-psoc-3


Here is a BLE application -

https://www.embedded.com/print/4458293



Regards, Dana.

[Photon939]

There is a posted project here, if you have loaded Creator on you
PC.


http://www.cypress.com/forum/psoc-3-known-problems-and-solutions/servo-motor-interface-psoc-3


Here is a BLE application -

https://www.embedded.com/print/4458293



Regards, Dana.

These projects are not applicable for my project, these are for hobby RC servos which do not have position feedback.

[Photon939]

You may wish to take a look at Microchip AN532 which describes a servo motor control system using a PIC17C42 and a PLD.

This was used very successfully as the basis of the dual servo motor controller in the Losmandy Gemini-1 telescope control system.

The 17C42 is now somewhat dated, but the concepts and the code are still valid and it could readily be ported to a newer PIC (beware clock rate differences).

HtH
David Partridge

Thanks this is the type of application I am looking for. I do have a PSOC from Cypress I got at world makerfaire that might allow me to do all of these digital functions within one chip. I hope I can get the hang of it after being an Arduino scrub for ages.