Which Motor Driver IC to select for driving a 12V 2.5A Solenoid

[gada]

Posted on December 15, 2013 at 19:47

Hello,

I wanted to operate a solenoid of 12V 2.5A rating. 

I would like to know what kind of Motor Driver IC would be suitable for it (controlling through pwm). I am confused about RMS Current and Peak Current rating of the ICs.

Also what if I select an IC who has ampere rating higher than the solenoid. will it damage the solenoid.

thanks

[Enrico Poli]

Posted on December 16, 2013 at 13:28

Hello,

In general the current rating (rms or DC) of the IC should be greater than your target output current, in your case 2.5 A.

If you want to actively control the output current you need an IC with integrated current control such as the L6207/27. Otherwise you can control the solenoid current using an open loop method applying the proper voltage through a PWM modulatio (Vout,mean = VS x DutyCycle, Iout,mean = Vout,mean/Rsolenoid). In this case you can use the L6206/26 setting the overcurrent threshold just above the current rating of the solenoid (this way it is protected from electrical overstress).

You should also consider the power dissipation of the IC in order to avoid thermal issued.

More details are available on the application notes of the ICs.

Regadrs

Enrico

[gada]

Posted on January 21, 2014 at 20:25

Hello. I Had few days back, connected the L6206 IC With a MicroController giving out PWM signals. to the input pins of the L6206. Firstly I was using just the first bridge and had kept the 2 bridge pins open(floating). The circuit diagram is the one given in the data sheet. I blew 2 L6206 with this setup. The reason is unknown. 

Then I connected all the unused pins (2nd bridge) to ground  and checked the output. It worked. 

But I am still not sure what made the first two ICs non working. By non working i mean that when i connect it into the circuit their +ve and -ve points come shorted. 

Also within all this the micro controller also getting hot, which shouldnt actually happen. If the drive provided by the mcu is 0 to 3.3v what can be done to protect the mcu from the high voltage on the driver IC. 

Any Suggestions on my working techniques with L6206 ICs would be welcomed.

Best Regards 

kASHYAP GADA

gada.kashyap(@)gmail(.)com