Trying get motor running using L6208N

[dairymtu1]

Posted on December 11, 2006 at 17:03

Trying get motor running using L6208N

[dairymtu1]

Posted on May 17, 2011 at 10:13

Hi, I'm trying get the L6208N to run my motor. I have all the input logic signals, even use the DAC to create the microsteps sine wave. However the motor doesnt seem to run just stall. I reduce the delay to just 100Hz and you could see the motor moving fwd then back and keeps going on.

My steps/clock seems to follow correctly. Only thing i could thing of is that the noise is probably disrupting my signal. THe output current doesnt look good at all. In addition, i compared the signals RCA and RCB to the ST Eval board and i have a Sawtooth coming out of it compared to just DC on the evalbd. What am i doing wrong here? Use the same values evalbd has (almost all), logic input levels that are low and high are within threshold mins/max, calculated shunt and voltage going into, my VCP is working fine etc. Only thing i could think of is noise issue so i put caps around to get rid of the spikes. Any suggestions appreciated Thanks

[info45]

Posted on May 17, 2011 at 10:13

Hy,

I haved used L6208 without problems. For motor start and stop I needed to used acceleration/decelleration ramps. If You start the mouvement the motor without the ramp, it can be stall and don't move or in opposite direction. In these case the motor produce noise. By

[dairymtu1]

Posted on May 17, 2011 at 10:13

it looks like my motor is in wave drive mode. I put a pull down resistor on the half/full mode pin but still does wave drive. Is it possible that the MOSFET bridge is being shut off by the 'One shot Monostable' bridge?

All it says in the manual is that if Vsense > Vref the oneshot kicks in and shuts the bridge off. Maybe someone could clarify

[dairymtu1]

Posted on May 17, 2011 at 10:13

When i look at my motor current, i have some gap between the fwd pulse and rev pulse. Why is that? I use 1000pF and 25kOhm under the RCA RCB. After the fwd pulse is done, a gap of about 660us at zero and then it starts the rev pulse.

[ This message was edited by: dairymtu on 08-12-2006 19:55 ]