Turn-on voltage of mos diode

Mos diodee turn-on voltage.

The turn-on voltage (YGS (th)) is also known as the "gate threshold voltage". The choice of this value here is mainly related to the operational amplifier used as a simulator. VMOS is not like BJT, the gate relative to the source requires a certain voltage to turn on, the lowest value of this voltage (usually a range) is called the turn-on voltage, the saturation on-voltage is generally about twice the open voltage, if the opening voltage given in the technical manual is a range, take the maximum value. The opening voltage of VMOS is generally about 5V, and the type of low opening voltage is about 2V. If 5.5V D is used as the operational amplifier, the maximum output level is about 2.5V. Even if the VMOS with low turn-on voltage is used, such as the 2SK2313 in figure 2.6, the lowest driving level is at least 5V. Therefore, according to the above selection criterion for the operational amplifier, the 5.5V operational amplifier cannot be used in practice, and the lowest recommended operating voltage is ±6V, because the highest output level of the operational amplifier is usually slightly lower than the working voltage. This is true even for rail-to-rail input / output operational amplifiers that have been widely used in recent years.

Of course, P-channel VMOS can also be used, but the driving method is the opposite of N-channel. However, until now, the general current specification of the VMOS that communicates with N with the same series of P communication with the same voltage specification is lower than that of N-channel, while the saturation on-voltage is higher than that of N-channel. Therefore, N channel is chosen instead of P channel.