High Side Mosfet Switch Circuit

The opposite of the low side switch is the high side switch.

High side mosfet switch circuit.

While designing the ups circuits mosfet were used in the inverter circuits. Drive circuits for the high side switches are called high side drivers and are more complicated than low side drivers because of the required voltage translation to the supply and because it is more difficult to turn off a floating switch. Firsly in fig 4 6 13 the resistor r4 whose purpose is to discharge any remaining potential on the gate at switch off is now connected to the positive supply rail instead of to ground. Ir2110 which is arguably the most popular high low side mosfet driver features a high side driver and a low side driver in a single device.

Ir2110 is a high low side gate driver ic which is used with power mosfet and igbt. One fault common to such circuits has been the excessive crossover current during switching that may occur if the gate drive allows both mosfets to be on simultaneously. This transistor connects between v and the load. N channel p channel 15.

A high side p channel mosfet and a low side n channel mosfet tied with common drains figure 5 make a superb high current ªcmos equivalentº switch. In this instance the mosfet switch is connected between the load and the positive supply rail high side switching as we do with pnp transistors. Yes but there are issues. In a p channel device the conventional flow of drain current is in the negative direction so a negative gate source voltage is applied to switch the transistor on.

A circuit for a typical high side switch using a p channel mosfet is shown in fig. For an n channel mosfet the source connects to ground and the drain connects to the negative side of the load. I ve written a detailed tutorial regarding the use of ir2110. While you can use a jfet for this circuit an enhancement mode mosfet works better.

The n channel mosfet of a buck converter is a high side switch. Notice the similarities and differences between figs. Ir2117 for example is one driver that contains a single driver that can be used to drive a high side mosfet driver. The mosfets were used as high side switches in the circuit.