Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [pmos]

A p-channel metal-oxide semiconductor (pMOS) transistor which has has p-type carriers used in the channel. The channel is established by a negative voltage on the gate which inverts the substrate (NWell) under the gate which turns the device on. The term may also be used to describe logic circuits built around pMOS transistors.

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High Side P Mosfet Circuit

I'm designing a circuit to use a P mosfet as a high side switch. The supply will be either 12v or 24v. The circuit is being designed for 8 amps max current draw. Does this circuit look exceptable? EDIT: I've revised the circuit. The PWM will be no…
jonfarrugia
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How are PMOS equations different than NMOS's?

I have been googling about it and I see lots of different ways such as only flipping the signs (< becomes >) and switching variables (VGS becomes VSG). Some people even say just put absolute value without changing anything and putting absolute for…
captain
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Why do I need a pullup resistor at the gate when using a pmos as a high side switch

Very quick question: Assuming I am using a pmos as a high side switch and my supply voltage and the voltage at the gate I want to switch the transistor with (V_logic) are the same. I usually find something like this: Now I actually don't quite…
Axodarap
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P-MOS Selection for 12v application

First off, let me state that I am pretty new to FETs, so I'm still wrapping my head around the different characteristics. The circuit below is a switch that will trigger a 12v (VIN=12v) signal to be constantly on, based on input from an MCU…
t3ddftw
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Correct PMOS Vgs?

Please image attached. Is there a mistake on the solutuion as it seem that for the PMOS Vgs = Vs-Vg?? Isn't it supposed to be Vgs = Vg-Vs? Thanks
Arsenal123
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PMOS circuit Voltages doubt in LTSPICE

I am trying to understand basics about PMOS transistor such as understand Vth value when the transistor goes to saturation and permits the drain to flow completely. My circuit is this and the voltages are negative but the Voltage Sources (Vgs, and…
imt_blake
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P-MOS high side switch problem

I have designed a PCB that utilizes a P-MOS as a high-side switch to control a 48 V battery using the following circuit. The P3 connector is connected to a momentary switch and a 5 V LED. The intended function is as follows: pressing the button (P3)…
Hamed
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PMOS turn on and turn off condition

I am planning to use the FDC6312P (PMOS) in my circuit and want to know the turn on and turn off condition for the PMOS. I looked at the datasheet to find the turn on and turn off condition but too much information is hurting my beginners brain.…
Adnan
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Switch capacitive load with a PMOS

I want to switch a capacitive load with a PMOS once while running, then the continous current is maximum 13mA. The capcitive load is 2x10uF X5R, 1x1uF X5R and 1x100nF X5R, so pretty low series resistance and so I expect a pretty high current. Since…
HansPeterLoft
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PMOS as a load switch

I have designed the following circuit using a PMOS (FDC6312P) as a load switch. The gate of the PMOS will be driven by an NPN transistor that can be controlled using the MCU's GPIO. I need to make sure that upon power-on, the load switch remains…
Adnan
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Making a PMOS act as a low voltage drop diode

I would hope to replace my Schottky diode that is acting as a as or diode. I do not like how high voltage drop the Schottky diode is making thus I would like to switch to a MOSFET. And the simplest circuit I could with a MOSFET kind of like this. I…
DrakeJest
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PMOS device in low-side switch

For most low-side switches I've seen, an NMOS device is used. I am wondering, is it not possible to use a PMOS device in a low-side switch?
AlfroJang80
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Output voltage for pmos with Vt= -0.8

simulate this circuit – Schematic created using CircuitLab What is VX? I am having confusion between 2.8 V or 3 V. Thank you for your help.
Ravi
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What would happen if there is no ground in a PMOS inverter?

I understand why when there is a ground you need a resistor or an NMOS but what if there were no ground at all and simply A goes high, B is 0, A goes low, current flows from VDD to B through the p channel. What's the reason this won't work?…
Lewis Kelsey
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PMOS Falling Time

I have established a circuit which has a -7V,+7V 16kHz square wave and my aim is obtaining 0V,+1V 16kHz square wave output signal. To do this, i have used a TI SN75189ADR and DMP4051LK3-13 pmos as i mentioned below; Because of the inverting…
bieaisar
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