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Can you use a Zener on a MOSFET?
Most MOSFETs won’t be able to handle that and will burn out (or blow up), or they would if it weren’t for the Zener. The Zener will effectively clamp Vgs at 15V, which the MOSFET WILL be able to handle.
How does the Zener diode work as a diode?
The Zener also acts as a regular diode, clamping Vgs at -0.7V or thereabouts, instead of allowing it to reach -10V; as it would do if OUTB stayed on for a long time, then was switched off. Here is a fragment from one of my project where I use mosfet as reverse polarity protection (for battery input):
What is the Max Voltage for a MOSFET gate?
The gate voltage is +10V maximum, 0V minimum and VPP1 and VNN1 are +100V and -100V respectively. Zener voltage for the diode is 15V. \\$\\begingroup\\$ Well, to protect the gate of the MOSFET from over-voltage, the Zener voltage rating should be lower than the MOSFET Vgs absolute max rating (from the MOSFET datasheet).
Can a Zener be replaced with a 13v battery?
A good way to picture it is if the zener is conducting with current flowing from cathode to anode, (which it will for DC inputs > 13V) replace it with a 13V battery with the negative terminal where the anode was and the positive terminal at the cathode and it will become clear that M1 will be driven to saturation.
How does the Zener diode protect the load?
It is the voltage value where the Zener diode will act as a close circuit and protect the load from overvoltage. For the above example in Pspice, the Zener voltage is 6.8V. There will be some situations where the targeted Zener diode voltage is not available. In such cases, a close value of the Zener diode can be chosen.
How is a MOSFET protected in a circuit?
The grounding or shorting rings are removed after the MOSFET is connected in the circuit. Sometimes conducting foam is applied between the leads Some MOSFETs are protected by built-in Zener diodes in parallel with the gate and source, as shown in figure.
What should the Zener voltage be for PSpice?
For the above example in Pspice, the Zener voltage is 6.8V. There will be some situations where the targeted Zener diode voltage is not available. In such cases, a close value of the Zener diode can be chosen. For example, for overvoltage protection up to 7V, a 6.8V Zener diode is a close value.
Is there a Zener diode between gate and source?
Putting a Zener diode between G and S looks like a common technique (among many others http://www.diystompboxes.com/smfforum/index.php?topic=100760.0#msg888061, https://electronics.stackexchange.com/questions/187075/mosfet-gate-source-protection-question ). But does this technique also work when the chip is out of circuit?
Which is diode between gate and source in N-CH MOSFET?
Re: Zener diode between Gate and Source in N-ch MOSFET. Enough to touch freely? ESD destroys a MOSFET by creating too much voltage between gate and source, which permenently breaks down the gate isolation. The diode prevents this, as long as it is there, so it will work even outside of the circuit.