PWM current control in stepper motor

[thai]

microstep irf530

I'm a new comer with analog design. I'm going to design micro stepper motor drive. some problems i meet in the way i control current through coils. Current I use method PWM to control current, please show me some place can i get more good knowledge about PWM in step motor control, or can you show me some circuit control current by PWM in Bipolar motor stepper.
Thank you very much!

 

[picotube]

current pwm microstepping circuit

Pls try the following links first:

 

[thai]

stepper pwm current control

Now, my goal of this project control bipolar step motor (micro step mode 1/16, 1/32) at 8A with MOSFET IRF530, IR2112S, anyone can show me a good PWM current chopper circuit to handle it.
Thanks,

 

[nicleo]

stepper motorcircuitcontrol

Now, my goal of this project control bipolar step motor (micro step mode 1/16, 1/32) at 8A with MOSFET IRF530, IR2112S, anyone can show me a good PWM current chopper circuit to handle it.
Thanks,

You may wish to read this articles from Allegro:

FULL-BRIDGE PWM MICROSTEPPING MOTOR DRIVER
**broken link removed**

MONOLITHIC, PROGRAMMABLE, FULL-BRIDGE MOTOR DRIVER INTEGRATES PWM CURRENT CONTROL AND ‘MIXED-MODE’ MICROSTEPPING
**broken link removed**

3955SB Product Evaluation Kit
This demo board will drive both windings of a bipolar stepper motor in a microstepping mode. The schematic of the demo board is provided.
**broken link removed**

‘SMART’, CONSTANT-TORQUE, MICROSTEPPING DRIVE CIRCUITRY FOR UNDER $10
**broken link removed**