DMOS Driver L6208 For bipolar stepper motor Heating issue..

[development2]

Posted on August 11, 2014 at 12:34

hi,

I am trying to drive bipolar stepper motor having 2.8A/phase current requirement using EVAL6208PD , after exceeding current limit of 1.5A drive IC get heated. Is it possible to drive bipolar stepper motor having current requirement 2.8A/phase using EVAL6208PD ?For my application , current requirement is 2.8-3A/phase then please tell me L6208 is suitable for it or not?? #l6208

[Enrico Poli]

Posted on August 21, 2014 at 14:45

Hello,

the problem is the power dissipation. Driving a 2.8 A current with the L6208 you have a powert dissipation on the IC of about 15.7W (Pd = I^2 x (Rds(ON)HS + Rds(ON)LS) x 2). In order to dissipate all the heat and keep the device in a safe operating temperature, let's say 125°C starting from an ambient temperature of 25°C, you need a thermal resistance junction to ambient of at least 6°C/W (100°C / 15.7 W). This values can be only obtained using an heatsink (and with some effort). Kind Regards Enrico

[development2]

Posted on August 22, 2014 at 09:22