If I dont use schottky or TVS diode between output of the IC and ground, do I damege the IC because of back emf voltage ? (VND5E160AJTR-E)

[bülent küpeli]

Hi all,

I am using VND5E160AJTR-E for driving a inductive load. The values of inductive and resistive load is 15 mH and 12 ohm. As you know happening back emf pulse while driving a inductor load and I dont use schottky diode for cutting off back emf because back emf pulse provides fast closing on the load and this stiuation is require for my circuit. Also I dont use TVS diode because when I use it, I fail CE102. Actually I wonder that does the back emf voltage damage or not VND5E160AJTR-E IC. Especially current sense circuit in the IC and I saw this value (VCSENSE Current sense maximum voltage VCC-41+VCC) on the table 3 of datasheet. Is there a diode in the IC and this means that the IC cut off back emf voltage between VCC / + VCC - 41 V ? or is this value maximum rate ? In brief If I don't use schottky or TVS diode between output of the IC and ground, do I damage the ICU because of back emf voltage ?

[KiptonM]

Have you measured the peaks of the back EMF with a high speed oscilloscope? How high does the BACK EMF go?

Those numbers in Table 3 are ABSOLUTE maximum, meaning you will damage the IC if you exceed them.

You do not say what your VCC is. If it is 12V or 28V then put in a TVS higher than that voltage.

How high above your voltage do you need the back EMF to be to work as you say you need? You can get a TVS for that voltage.

I think you may be doing something wrong. But I do not have enough information to say what that is.