How to determine the voltage supply value for Vss pin?

[etiquoe]

i'm gonna use IR2110 IC to drive my H-bridge for my 24 V BLDC motor driver.
but i dont understand about using Vss pin.
how to determine the voltage supply value for Vss pin?

anyone can help?

 

[keith1200rs]

Vss for IR2110

Vss is the ground pin: 0V.

Keith.

 

[Tahmid]

Vss for IR2110

Hi,
VSS and COM pins are where you connect the ground. VSS is for the chip supply ground, and common is for low side drive.

The maximum VDD to VSS voltage is +25.

Hope this helps.
Tahmid.

 

[etiquoe]

Re: Vss for IR2110

from the datasheet and AN 978, Vss is connected to Vdd with capacitor.
is it a must?
and how to calculate value of the capacitor?

 

[FvM]

Vss for IR2110

You surely should have some Vdd bypassing. With separated Vdd and Vcc supply, 0.1 uF should be enough for Vdd, but I would prefer 1 uF ceramic near to the chip. In case of common supply, a larger bypass cap (e.g. 10 uF) is suggested by the datasheet anyway.

As another comment, although 3V Vdd supply is allowed by the datasheet, you won't to use voltages below 5 V if you consider the timing diagrams. The actual chip behaviour can be even worse, according to my observations.

In case of separated Vdd and Vcc supplies, separated control (VSS) and power (COM) grounds may be used as well. But only a limited voltage difference is allowed between both ground pins. IRF document DT97-3 gives some considerations regarding safe operation of the IR2110. Connecting both ground pins near to the IR2110 should always work, of course.

 

[etiquoe]

Re: Vss for IR2110

In case of separated Vdd and Vcc supplies, separated control (VSS) and power (COM) grounds may be used as well. But only a limited voltage difference is allowed between both ground pins

so, is it better to have Vss and COM connected?