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Electronics => Beginners => Topic started by: hsn93 on March 11, 2018, 06:40:27 am

Title: Complementary MOSFET Motor Controller
Post by: hsn93 on March 11, 2018, 06:40:27 am

hello,

i was looking in pmos and while reading post in electronics-tutorial found this page:

https://www.electronics-tutorials.ws/transistor/tran_7.html (https://www.electronics-tutorials.ws/transistor/tran_7.html)

(https://snag.gy/UDKkaw.jpg)

the question is: the Vin has to be ( +vdd for logic 1 ) and ( -vdd for logic 0 ) right ?

as if it was for example ( TTL or cmos) the N mosfet will be on even the Vg was ground .. as the voltage at source is negative right ??
(https://snag.gy/aKtckP.jpg)

Title: Re: Complementary MOSFET Motor Controller
Post by: rstofer on March 12, 2018, 09:13:28 pm

You got it right.

This is a particularly bad way to do the switching because it is going to be difficult to avoid shoot-through.  The N channel device turning off will overlap with the P channel device turning on and vice versa.

The MOSFET part is ok but the switching signals need to guarantee no overlap.

A full H-bridge is a better solution.