Online simulation of the p-моп-транзистор circuit

This is a simple model of a p-type MOSFET. The source is at 5 V, and the gate and drain voltages can be adjusted using the sliders on the right. Normally no current flows unless the gate voltage is at least 1.5 V below the source voltage. (Threshold = -1.5 V.) Thus, if the gate is below 3.5 V, current flows; otherwise it does not. When the gate and drain voltages are low enough, the MOSFET is in saturation, and the current stays constant regardless of the drain voltage. If you raise the drain voltage relative to the gate, the MOSFET is in the linear region, and the current is roughly linear with respect to the source-drain voltage difference. By slowly moving the drain voltage slider back and forth, you should see the boundary between the linear and saturation regions. Try this with other gate voltage settings.

This page is a utility for simulating p-моп-транзистор online with specified initial values.