P Channel Mosfet High Side Switch
The p channel high side switch therefore solves the problem of using an n channel mosfet for high side switching.
P channel mosfet high side switch. Usually the source pin must be more positive than the drain however this isn t true when using a p mosfet to provide reverse polarity protection for instance. No charge pump is required for driving the high side switch. In this case use a p channel mosfet to turn the relay on from the arduino s i o pin. P channel mosfets generally have a higher r dson compared to n type mosfets having a similar internal chip size.
Then the p channel mosfet is used to switch the positive supply to the motor for forward direction high side switching while the n channel mosfet is used to switch the negative supply to the motor for reverse direction low side switching. However this cure can also have some side effects. P channel mosfet high side switch here s my schematic and board design for a simple high side switch using a p channel mosfet. There are a variety of configurations for driving the two mosfets with many different applications.
The current necessary for the relay coil is too high for an i o pin but the coil needs 5v to work. It s a simple circuit that has a input for positive and negative and an output for positive and negative connections. Because of how transistors work these can be a little more difficult to use in an arduino or raspberry pi circuit. Used as a high side switch a p channel mosfet in a totem pole arrangement with an n channel mosfet will simulate a high current high power cmos complementary mos arrangement.
This transistor connects between v and the load. If your load voltage is higher like 12 or 24v then you might want to use an n channel mosfet in a low side configuration. It can easily be driven by the mcu via a level shifter. The opposite of the low side switch is the high side switch.