Drain current mosfet

A MOSFET that normally turns ON without applying any gate voltage when you connect is known as a depletion mode MOSFET. In this MOSFET, the flow of current is from the drain terminal to the source. This type of MOSFET is also known as normally on the device. Once a voltage is applied at the gate terminal of the MOSFET, the drain to the source ...

Jul 25, 2016 · Thus, channel-length modulation means that the saturation-region drain current will increase slightly as the drain-to-source voltage increases. So we need to modify the saturation-region drain-current expression to account for channel-length modulation. We do this by incorporating the incremental channel-length reduction into the original ... The metal-oxide-semiconductor field-effect transistor ( MOSFET, MOS-FET, or MOS FET) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which determines the conductivity of the device.Jun 7, 2020 at 21:37. I studied the MOSFET chapter out of Microelectronics by D. Neaman. There the transconductance parameter was mentioned as being in the order of 200u - …A MOSFET also contains a BJT: If the drain current is high, then the voltage across the channel between the source and the drain can also be high, because RDS(on) R D S ( o n) is non-zero. If it's high enough to forward-bias the body-source diode, you don't have a MOSFET anymore: you have a BJT. That's also not what you wanted.A MOSFET also contains a BJT: If the drain current is high, then the voltage across the channel between the source and the drain can also be high, because RDS(on) R D S ( o n) is non-zero. If it's high enough to forward-bias the body-source diode, you don't have a MOSFET anymore: you have a BJT. That's also not what you wanted.May 5, 2017 · R DS (on) stands for “drain-source on resistance,” or the total resistance between the drain and source in a Metal Oxide Field Effect Transistor, or MOSFET when the MOSFET is “on.”. R DS (on) is the basis for a maximum current rating of the MOSFET and is also associated with current loss. All things being equal, the lower the R DS (on ...

2 Silicon limited drain current Usually, in every Power MOSFET datasheet the drain current limit is fixed by the package limit. It depends on the kind, number and the size of the wires that connect the drain and the source pads to the respective package pins. However, another important parameter definedthreshold voltage of the power MOSFET, drain current starts to flow. The gate voltage continues to rise to the plateau voltage VGP (VGSTH+ID/gFS), while the voltage across the DUT remains equal to VDC. The charge (Ig*time) needed to reach this state is QGS. Once the drain current reaches ID the drain voltage starts to fall.Jul 16, 2022 · Testing pulse drain current seems to work with a "welding" generator. I have used an Arduino nano to deliver "short" pulses (0.1 ms -> 1 ms, duty cycle <=0.1% ) and measure one voltage (one R ~ 0.1 Ohm for each MOSFET)-> pulse current, one BJT, and some (5) "paralleled MOSFET". Got easily 100 A with a simple power supply (3 A max) and some ... When using a MOSFET as a switch, you want to transition it rapidly through the region where the drain current is controlled by the gate-source voltage (as opposed to the drain current being either 0 (OFF, gate-source voltage < threshold) or set by external circuit elements (ON, Vgs >> threshold), in both directions.While some may think having to pay for insurance every month is dollar bills down the drain, if an incident occurs and you don’t have insurance, it can lead to major financial hurdles that may last for years to come. It seems though that th...inversion charge that carries the current • Drain-Source Voltage (V DS): controls the electric field that drifts the inversion charge from the source to drain Want to understand the relationship between the drain current in the MOSFET as a function of gate-to-source voltage and drain-to-source voltage.

of 1:1000 Schematically, this looks like two parallel FETs with common gate and drain connections, but separate source leads. An illustration of this configuration appears in Figure 1. The relative size of the two devices determines how current is split between source and mirror terminals. The ratio of source current to mirror current is ...−VDS, DRAIN−TO −SOURCE VOLTAGE (VOLTS) − I D, DRAIN CURRENT (AMPS) 6 2 0 1 Figure 1. On−Region Characteristics 0 24 10 1 0 6 Figure 2. Transfer Characteristics VGS, GATE TO SOURCE VOLTAGE (VOLTS) 0.02 79 0.04 0 Figure 3. On−Resistance vs. Drain Current and Temperature −ID, DRAIN CURRENT (AMPS) R DS(on), DRAIN − TO − …In simple terms, MOSFET current rating can be defined as the maximum amount of current a MOSFET can handle safely and optimally across its drain to source terminals, with its case temperature held below 40 °C. The Current rating is perhaps the most deceiving parameter on a MOSFET datasheet, since you cannot find any industry standard technique ...If the dV/dt across the MOSFETs drain to source is too high, it may charge CGD, which is the capacitance between drain and gate, inducing a voltage at the gate. The gate voltage depends on the pull-down resistor of the driver based on Equation (4). ... The drain current that flows with these conditions is 0.1/0.026 = 3.846 A. The maximum die ...The MOSFET (Metal Oxide Field Effect Transistor) is an active semiconductor device most widely used in Integrated circuits.It is a voltage-controlled device because the current between source and drain is controlled by the gate voltage. MOSFET is a unipolar device because the charge carriers that are responsible for current are either electron …

Free adobe reader for students.

Power MOSFETs generally have a R DS(on) value of less than 0.01Ω which allows them to run cooler, extending their operational life span. One of the main limitations when using a MOSFET as a switching device is the …Figure 7 Flyback with control IC with a depletion MOSFET, adjusted drain current Now the start-up time is independent of the input voltage. This circuit can be further optimized by adding a few SMD devices – see Figure 8. Application Note 5 of 10 V 1.0 2018-07-20The field-effect transistor ( FET) is a type of transistor that uses an electric field to control the flow of current in a semiconductor. It comes in two types: junction-gate FET (JFET) and metal-oxide-semiconductor FET (MOSFET). FETs have three terminals: source, gate, and drain. FETs control the flow of current by the application of a voltage ...A MOSFET is a four-terminal device having source (S), gate (G), drain (D) and body (B) terminals. In general, The body of the MOSFET is in connection with the source terminal thus forming a three-terminal device such as a field-effect transistor. MOSFET is generally considered as a transistor and employed in both the analog and digital circuits.Just have a few questions. When the MOSFET started to conduct and the instant drain current starts to increase, since the voltage across the gate drain capacitance cannot change instantaneously, the current from the signal source goes to the capacitor and clamps the voltage at the value and thereby maintaining voltage across the capacitor.

The MOSFET Constant-Current Source Circuit. Here is the basic MOSFET constant-current source: It’s surprisingly simple, in my opinion—two NMOS transistors and a resistor. Let’s look at how this circuit works. As you can see, the drain of Q 1 is shorted to its gate. This means that V G = V D, and thus V GD = 0 V.As the Gate terminal is electrically isolated from the main current carrying channel between the drain and source, “NO current flows into the gate” and just like the JFET, the MOSFET also acts like a voltage controlled resistor where the current flowing through the main channel between the Drain and Source is proportional to the input voltage. . Also like the …Key elements: Inversion layer under gate (depending on gate voltage) Heavily doped regions reach underneath gate ⇒ inversion layer to electrically connect source and drain 4-terminal device: body voltage important Circuit symbols Two complementary devices: n-channel device (n-MOSFET) on p-substrate uses electron inversion layerMar 16, 2021 · Yes, most mosfet datasheets have a graph like this one: (image from User:Krishnavedala at Wikipedia: MOSFET) From that graph, you can look at the datasheet at the specified gate voltage (GS) and drain voltage (DS) and read out the drain current. You could use Ohm's law to calculate an effective absolute resistance R = Vds/Id during those ... Jan 12, 2016 · 5. The drain current depends on carrier mobility (which decreases with increasing temperature by about -0.3 %/deg C); carrier concentration (which increases negligible with temperature), and threshold voltage (which decrease with temperature by about -2 mV/deg. C). At gate voltages just above the threshold voltage (say < 500 mV above), the ... The best FETs for current sources are those having long gates and consequently very low goss. The Siliconix 2N4340, J202, and SST202 exhibit typical g oss = 2 S at ... the drain current, I D, versus the source resistance, R S, in Figures 8, 9, and 10. Most plots include the likely worst case ID variations for a particular R S. For tighter currentFor drain-source voltages above +1 V, the MOSFET current increases linearity with increasing VDS. The higher the lambda value the higher the slope of the curve in this region. Say, for example, lambda = 0.05 V -1 , then one can see that the output current increases with increasing drain-source voltage at a rate of 20.314 휇 A/V.6 апр. 2020 г. ... 1 which depicts the continuous drain current as a function of mounting base temperature. Fig. 1 shows that for a Tmb of 75 °C, the maximum ...The MOS Transistor Structure Revisited. The MOS transistor structure consists of a metal, an oxide, and a semiconductor structure (hence, MOS). Consider an NMOS transistor with p-substrate and n+ diffusion wells as drain and source terminals. The oxide layer is made of SiO 2 and is grown over the channel between the drain and source.Feb 24, 2019 · The drain characteristics of a MOSFET are drawn between the drain current I D and the drain source voltage V DS. The characteristic curve is as shown below for different values of inputs. Why drain current of MOSFET is zero before threshold voltage? If the gate voltage is less than the threshold voltage, the current in the device is essentially ... A MOSFET that normally turns ON without applying any gate voltage when you connect is known as a depletion mode MOSFET. In this MOSFET, the flow of current is from the drain terminal to the source. This type of MOSFET is also known as normally on the device. Once a voltage is applied at the gate terminal of the MOSFET, the drain to the source ...

Leakage current due to hot carrier injection from the substrate to gate oxide. Leakage current due to gate-induced drain lowering (GIDL) Before continuing, be sure you're familiar with the basic concepts of MOS transistors that will prepare you for the following information. 1. Reverse-Bias pn Junction Leakage Current.

In a P-channel MOSFET, the source needs to be more positive than the drain, otherwise the terminals switch roles. That means that in figure 1, the bottom electrode is acting as the source even though it is supposed to be the drain. In this case, Vgs is -5, since the gate is at 0V and the source is at +5.Field-effect transistor. Cross-sectional view of a field-effect transistor, showing source, gate and drain terminals. The field-effect transistor ( FET) is a type of transistor that uses an electric field to control the flow of current in a semiconductor. It comes in two types: junction-gate FET (JFET) and metal-oxide-semiconductor FET (MOSFET).While some may think having to pay for insurance every month is dollar bills down the drain, if an incident occurs and you don’t have insurance, it can lead to major financial hurdles that may last for years to come. It seems though that th...Aug 13, 2013 · We begin the drain voltage measurement process by first reviewing equipment requirements. To measure switching voltage across the MOSFET, you will need a 100x voltage probe rated for at least 1000 V. The bandwidth of both the scope and probe used to view the drain voltage waveform should be 100 MHz or higher. In this region the MOSFET is ‘OFF’ as no current can flow from the source to drain. In order to allow current to flow freely from the source to drain, we need a conducting path. This conducting path is created when the MOSFET is operating in the saturation region. But in order to get to the saturation region we need to turn the …inversion charge that carries the current • Drain-Source Voltage (V DS): controls the electric field that drifts the inversion charge from the source to drain Want to understand the relationship between the drain current in the MOSFET as a function of gate-to-source voltage and drain-to-source voltage.drain-source voltage v. DS. of the MOSFET remains equal to V. DD. and the gate voltage v. GE . increase is almost the same as in the period from 0 to t. 1, which is expressed by Equation (1). (3) t. 2. to t. 3 (The MOSFET is switching.) As the reverse recovery current of the freewheel diode falls to zero, the drain current of the MOSFET reaches ...Power MOSFET Datasheet Explanation 9 -03 V1.1 March 2012 2.3 Safe operating area Figure 5 shows the drain current (I D) as a function of the drain-source voltage (V DS) with different pulse lengths. This is one of the most complicated but important figure that should not be ignored in the datasheet.

Zillow homes montana.

Parthenon friezes.

In this circuit, the V gs is the input signal applied between gate and source terminal, and we know that the change in drain current is linearly proportional to V gs.In this model, if you consider the effect of channel and modulation, then there will also be an output resistance (r0). If it is for a long length channel, then, as read in the Early Voltage section in …The Metal Oxide Semiconductor Field Effect Transistor (MOSFET) is one type of FET transistor. ... In this region drain current is zero and the transistor acts as ...100 A N-Channel 100 V MOSFET are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for 100 A N-Channel 100 V MOSFET. Skip to Main Content (800) 346-6873 ... Id - Continuous Drain Current. Rds On - Drain-Source Resistance. Vgs - Gate-Source Voltage. Vgs th - Gate-Source Threshold Voltage. Qg - Gate Charge.Continuous source-drain diode current IS MOSFET symbol showing the integral reverse p - n junction diode-- 5.6 A Pulsed diode forward current a ISM-- 20 Body diode voltage VSD TJ = 25 °C, IS = 5.6 A, VGS = 0 V b-- 2.5 V Body diode reverse recovery time trr TJ = 25 °C, IF = 5.6 A, dI/dt = 100 A/μs bAbstract. In this chapter, we discuss the leakage current mechanisms present in FinFET. These leakage mechanisms include weak-inversion current, gate-induced source and drain leakages known as GISL and GIDL, respectively, gate oxide tunneling and all its components, and impact ionization leakage. Weak-inversion current is the most important ...4 DERIVATION OF MOSFET I DS VS. V DS + V GS n=10^17 n=10^15 source drain Figure 2. Concentration Contours in Linear Region. A uniform nar-row channel exists. n=10^17 n=10^15 source drain Figure 3. Concentration Contours in Saturation Region. Channel narrow near source and spreads out and widens near drain, said to be \pinched o ".IRFZ44N Pinout. The IRFZ44N is a N-channel MOSFET with a high drain current of 49A and low Rds value of 17.5 mΩ. It also has a low threshold voltage of 4V at which the MOSFET will start conducting. Hence it is commonly used with microcontrollers to drive with 5V. However a driver circuit is needed if the MOSFET has to be switched in …MOSFET or Metal Oxide Semiconductor Field Effect Transistor is a type of FET having four terminals namely Drain, Gate, Source and Body/Substrate. The body terminal is shorted with the source terminal leaving a total of three working terminals just like any other transistor. The MOSFET conducts current between its source and drain through a path ...Feb 1, 2021 · Leakage current due to hot carrier injection from the substrate to gate oxide. Leakage current due to gate-induced drain lowering (GIDL) Before continuing, be sure you're familiar with the basic concepts of MOS transistors that will prepare you for the following information. 1. Reverse-Bias pn Junction Leakage Current. MOSFET – Single, N-Channel, Small Signal, Gate ESD Protection, SC-75 ... Zero Gate Voltage Drain Current IDSS VGS = 0 V, VDS = 30 V 1.0 A Zero Gate Voltage Drain Current IDSS VGS = 0 V, VDS = 20 V, T = 85 °C 1.0 A Gate−to−Source Leakage Current IGSS VDS = 0 V, VGS = ±10 V ±25 A ….

The implementation of the current mirror circuit may seem simple but there is a lot going on. The simple two transistor implementation of the current mirror is based on the fundamental relationship that two equal size transistors at the same temperature with the same V GS for a MOS or V BE for a BJT have the same drain or collector current. To …One of the most prominent specifications on datasheets for discrete MOSFETs is the drain-to-source on-state resistance, abbreviated as R DS(on). This R DS(on) idea seems so pleasantly simple: When the FET is in cutoff, the resistance between source and drain is extremely high—so high that we assume zero current flow.2) every external voltage or current (e.g., 𝑣𝑖,𝑣 ,𝑖 ) is defined in precisely the same way both before and after the MOSFET is replaced with its circuit model is (e.g., if the output voltage is the drain voltage in the MOSFET circuit, then the output voltage is still the drain voltage in the small-signal circuit!).According to wikipedia, the MOSFET is in saturation when V (GS) > V (TH) and V (DS) > V (GS) - V (TH). That is correct. If I slowly increase the gate voltage starting from 0, the MOSFET remains off. The LED starts conducting a small amount of current when the gate voltage is around 2.5V or so.The line in the MOSFET symbol between the drain (D) and source (S) connections represents the transistors semiconductive channel. If this channel line is a solid unbroken line then it represents a “Depletion” (normally-ON) type MOSFET as drain current can flow with zero gate biasing potential.Working Principle of MOSFET. The main principle of the MOSFET device is to be able to control the voltage and current flow between the source and drain terminals. It works almost like a switch and the functionality of the device is based on the MOS capacitor. The MOS capacitor is the main part of MOSFET.Drain current depends on threshold voltage which in turn depends on v SB. Back-gate transconductance is: 0 < η < 3 is called the back-gate transconductance parameter. bulk terminal is a reverse-biased diode. Hence, no conductance from the bulk terminal to other terminals. Lecture13-Small Signal Model-MOSFET 4 MOSFET Small-Signal OperationLED Cube - Drain Current Resistor for MOSFET Switch. 1. Drain to Source Current Waveform on Mosfet is Slow. 0. Electronic load MOSFET drain to source current suddenly increases. 1. MOSFET operating point in linear mode. 1. MOSFET on condition - Relationship between drain-gate voltage and drain-source voltage? 1.Anybody tell me how to calculate n channel mosfet drain current. Dec 27, 2012 #2 H. hemnath Advanced Member level 3. Joined Jun 24, 2012 Messages 700 …Jul 25, 2016 · Thus, channel-length modulation means that the saturation-region drain current will increase slightly as the drain-to-source voltage increases. So we need to modify the saturation-region drain-current expression to account for channel-length modulation. We do this by incorporating the incremental channel-length reduction into the original ... Drain current mosfet, Enhancement Mode MOSFET - The Enhancement Mode Metal Oxide Semiconductor Field Effect Transistor (EMOSFET) is a three-terminal Device viz. Source (S), Gate (G) and Drain (D). The EMOSFET is a voltage controlled device.The EMOSFET can be operated in the enhancement mode only. The EMOSFET has no physical …, , Look for "Logic level power MOSFETs N-Channel" It then comes down to low Drain- Source resistance (remember Power lost = I^2 * R) and the ability to handle the amount of current you want to switch at the voltage you want to switch. Look for a graph that shows you the Drain current for a particular Gate source voltage., Working Principle of MOSFET. The main principle of the MOSFET device is to be able to control the voltage and current flow between the source and drain terminals. It works almost like a switch and the functionality of the device is based on the MOS capacitor. The MOS capacitor is the main part of MOSFET. , The MOS Transistor Structure Revisited. The MOS transistor structure consists of a metal, an oxide, and a semiconductor structure (hence, MOS). Consider an NMOS transistor with p-substrate and n+ diffusion wells as drain and source terminals. The oxide layer is made of SiO 2 and is grown over the channel between the drain and source., If you open mosfet hard, say Rdson is 0.85mOhms. In case of 1000A the Vds will be less than 1V, so you have to look at the left side of graph. There is no line for 100ms pulse, so you have to interpolate between DC and 10ms pulse. The safe current is much lower than 1000A. It is like 400A., The channel between drain and source acts as a good conductor with zero bias voltage at gate terminal. The channel width and drain current increases if the gate voltage is positive and these two (channel width and drain current) decreases if the gate voltage is negative. Enhancement Mode. The Enhancement mode MOSFET is …, Aug 13, 2013 · We begin the drain voltage measurement process by first reviewing equipment requirements. To measure switching voltage across the MOSFET, you will need a 100x voltage probe rated for at least 1000 V. The bandwidth of both the scope and probe used to view the drain voltage waveform should be 100 MHz or higher. , The main principle of the MOSFET device is to be able to control the voltage and current flow between the source and drain terminal using the voltage applied at the gate terminal. The semiconductor surface at the below oxide layer, which is located between the source and drain terminal, can be inverted from p-type to n-type by the application ..., The Total Gate Charge (Qg) is the amount of charge that needs to be injected into the gate electrode to turn ON the MOSFET. The smaller this value, the lower the switching loss and the higher the switching speed that can be achieved. ... the drain side supply voltage (V DD) and drain current (I D) are fixed, and the minimum amount of charge ..., The field effect transistor is a three terminal device that is constructed with no PN-junctions within the main current carrying path between the Drain and the Source terminals. These terminals correspond in function to the Collector and the Emitter respectively of the bipolar transistor. The current path between these two terminals is called ..., maximum continuous drain current, there would be no bonding wire limitation issue. Datasheet condition is an ideal condition which gives us the maximum Id the MOSFET can get. In reality the MOSFET usually soldered on a finite size PCB with limited convection for heat releasing. Therefore we simulated the third case with MOSFET mounted on a 1, MOSFET drain current spec. MOSFET drain current spec. Posted by electrolust on 01 Feb, 2017 00:39. I'm looking at a specific part, NXP PMV20XNEA ..., DS For low values of drain voltage, the device is like a resistor As the voltage is increases, the resistance behaves non-linearly and the rate of increase of current slows Eventually the current stops growing and remains essentially constant (current source) "Linear" Region Current GS > V Tn S G V DS ≈ 100mV y p+ n+ n+ x p-type Inversion layer, Jean Rubillon 41 6 N-channel current flows from drain to source is that when the transistor is OFF the intrinsic diode of the transistor prevent the current from flowing from source to drain. How is it possible? in the datasheet has been explained, the mosfet is off and the current passes through body diode from source to drain, A MOSFET that normally turns ON without applying any gate voltage when you connect is known as a depletion mode MOSFET. In this MOSFET, the flow of current is from the drain terminal to the source. This type of MOSFET is also known as normally on the device. Once a voltage is applied at the gate terminal of the MOSFET, the drain to the source ..., Begin the drain current measurement process by inserting a wire loop to place the current probe into the circuit. Insert the loop into the circuit so that only the drain current runs through it., A leakage current is the most critical parameter to characterize heavy ion radiation damage in SiC MOSFETs. An accurate and refined analysis of the source and …, – no current flow between source and drain when voltage between source and drain is applied (v DS >0) – There is a depletion region between the p (substrate) and n+ source and drain regions • Apply a voltage on v GS > 0 – Positive potential on gate node pushes free holes away from the region underneath the gate and leave behind a , When the transistor is ON, the current can flow in either direction as the diode is effectively shorted by the Rds (ON) of the drain to source channel. Similar effect takes place in a P-Channel transistor. In the shown circuit the N-Channel FET diode prevents current to flow from the output back to the input in a paralleled supplies configuration., Continuous source-drain diode current IS MOSFET symbol showing the integral reverse p - n junction diode-- 28 A Pulsed diode forward current a ISM - - 110 Body diode voltage VSD TJ = 25 °C, IS = 28 A, VGS = 0 V b-- 2.5V Body diode reverse recovery time trr TJ = 25 °C, IF = 17 A, dI/dt = 100 A/μs b, STRUCTURE OF A MOSFET Lateral Channel Design The drain, gate, and source terminals are placed on the surface of a silicon wafer. This is suitable for integration, but not for obtaining high power ratings because the distance between source and drain must be large to obtain better voltage blocking capability. The drain−to−source current is, A French drain is an effective and efficient way to divert water away from your home and yard. It can help prevent flooding and water damage, as well as improve the overall drainage of your property., The field-effect transistor ( FET) is a type of transistor that uses an electric field to control the flow of current in a semiconductor. It comes in two types: junction-gate FET (JFET) and metal-oxide-semiconductor FET …, Jul 25, 2016 · Thus, channel-length modulation means that the saturation-region drain current will increase slightly as the drain-to-source voltage increases. So we need to modify the saturation-region drain-current expression to account for channel-length modulation. We do this by incorporating the incremental channel-length reduction into the original ... , Before, we go over the construction of N-Channel MOSFETs, we must go over the 2 types that exist. There are 2 types of N-Channel MOSFETs, enhancement-type MOSFETs and depletion-type MOSFETs. A depletion-type MOSFET is normally on (maximum current flows from drain to source) when no difference in voltage exists betweeen the gate and source ..., Sep 2, 2016 · One of the most prominent specifications on datasheets for discrete MOSFETs is the drain-to-source on-state resistance, abbreviated as R DS(on). This R DS(on) idea seems so pleasantly simple: When the FET is in cutoff, the resistance between source and drain is extremely high—so high that we assume zero current flow. , Just have a few questions. When the MOSFET started to conduct and the instant drain current starts to increase, since the voltage across the gate drain capacitance cannot change instantaneously, the current from the signal source goes to the capacitor and clamps the voltage at the value and thereby maintaining voltage across the capacitor., Mar 14, 2017 · If you open mosfet hard, say Rdson is 0.85mOhms. In case of 1000A the Vds will be less than 1V, so you have to look at the left side of graph. There is no line for 100ms pulse, so you have to interpolate between DC and 10ms pulse. The safe current is much lower than 1000A. It is like 400A. , If you will ever find a magic MOSFET that has a drain-source voltage drop of zero at any measurable current through the channel at any operation mode then let me know immediately. That would be a straight way to a near 100% efficient DC-DC converter circuit and to an enormous success on the power supply market., If you open mosfet hard, say Rdson is 0.85mOhms. In case of 1000A the Vds will be less than 1V, so you have to look at the left side of graph. There is no line for 100ms pulse, so you have to interpolate between DC and 10ms pulse. The safe current is much lower than 1000A. It is like 400A., ON: current flows one direction (drain-source, through the FET and the second diode), but not the other direction (source-drain, because the second diode is pointing the wrong way) OFF: current won't flow either way, because whichever way you look there's a diode opposing the flow of current. Two MOSFETs in series, pointing opposite directions:, A MOSFET also contains a BJT: If the drain current is high, then the voltage across the channel between the source and the drain can also be high, because RDS(on) R D S ( o n) is non-zero. If it's high enough to forward-bias the body-source diode, you don't have a MOSFET anymore: you have a BJT. That's also not what you wanted.