60 volts for stud welding
since in an FET the value of the current depends upon the value of the voltage applied at the gate and drain...so it is known as voltage controlled device.. for example..in a mosfet..the current from drain to source depends upon the width of the depletion layer..which in turn depends upon the voltage applied on the gate.. so that is the reason
To switch off a MOSFET, you need to remove or reduce the gate voltage below the threshold voltage (Vgs(th)). This can be done by connecting the gate to ground or applying a negative voltage relative to the source in the case of a p-channel MOSFET. Once the gate voltage is below the threshold, the MOSFET will stop conducting, effectively turning it off. Additionally, using a pull-down resistor can help ensure the gate discharges quickly when switching off.
Because for creating channal we need voltage at gate if there is no voltage at ate then VGS=0 this mean no amplificatiion can be done.
If negative voltage is applied to the gate of a NMOS, it repels electrons from the channel region towards the bulk of the p-substrate and attaract holes from p-substrate towards the channel. The recombination between holes and electrons causes a deplation of majority carriers in the channel. Enough nagative gate voltage can cause the channel depleted of majority carriers and cuts off the current between the source and the drain. The least negative gate voltage causing this is called gate-source cut off voltage.
To find the gate-source voltage (VGS) in a Junction Field Effect Transistor (JFET), you can measure the voltage difference between the gate and the source terminals. In a typical configuration, the gate is reverse-biased, meaning it is at a lower potential than the source. If you know the source voltage (VS) and the gate voltage (VG), you can calculate VGS using the formula: VGS = VG - VS.
A; There is just no thyristor that can be turn off with the gate. Once on it will stay on until the holding current is reduced and or the voltage is reversed in polarity. The gate is only used to turn it ON never off.
A: Two conditions one the gate has current flowing trough the other is forward voltage breakdown
a FET, or Feild Effect Transistor. In a FET, the value of the current depends upon the value of the voltage applied at the gate and drain so it is known as a voltage controlled device. For example: In a MOSFET the current from drain to source depends upon the width of the depletion layer which in turn depends upon the voltage applied on the gate.
To switch off a MOSFET, you need to remove or reduce the gate voltage below the threshold voltage (Vgs(th)). This can be done by connecting the gate to ground or applying a negative voltage relative to the source in the case of a p-channel MOSFET. Once the gate voltage is below the threshold, the MOSFET will stop conducting, effectively turning it off. Additionally, using a pull-down resistor can help ensure the gate discharges quickly when switching off.
since in an FET the value of the current depends upon the value of the voltage applied at the gate and drain...so it is known as voltage controlled device.. for example..in a mosfet..the current from drain to source depends upon the width of the depletion layer..which in turn depends upon the voltage applied on the gate.. so that is the reason
A: Because that is the controlling lead of an thyristor. .To do it otherwise it will be on-off at hi voltage only
Because for creating channal we need voltage at gate if there is no voltage at ate then VGS=0 this mean no amplificatiion can be done.
In the usual circuit, a pulse of voltage on the gate electrode, providing a very small current, will cause a large current to flow from anode to cathode. The SCR will stay on until the anode current is reduced to zero (which may be because it's an AC supply). More at http://www.allaboutcircuits.com/vol_3/chpt_7/5.html ANSWER: By applying a gate current of significant magnitude the SCR will turn on, It not an amplifier it does not amplify current it just conduct with the gate current It is possible to have more gate current then current trough it, the shut off point need not be zero voltage it can be negative to the anode or the falls below the holding current
A: An scr is a 4 layer diode and has 3 terminals gate anode and cathode. To turn it on the gate must be positive with respect to the cathode and have enough voltage and current to turn it on. The turn on also depends on the load. Another possibility is to increase the potential cathode to anode until it will turn on but this mode is not predictable. Once on there only two way to shut it off. Remove to load below the holding current or momentarily reverse the voltage
If negative voltage is applied to the gate of a NMOS, it repels electrons from the channel region towards the bulk of the p-substrate and attaract holes from p-substrate towards the channel. The recombination between holes and electrons causes a deplation of majority carriers in the channel. Enough nagative gate voltage can cause the channel depleted of majority carriers and cuts off the current between the source and the drain. The least negative gate voltage causing this is called gate-source cut off voltage.
the anode-cathode voltage drops
To find the gate-source voltage (VGS) in a Junction Field Effect Transistor (JFET), you can measure the voltage difference between the gate and the source terminals. In a typical configuration, the gate is reverse-biased, meaning it is at a lower potential than the source. If you know the source voltage (VS) and the gate voltage (VG), you can calculate VGS using the formula: VGS = VG - VS.