What is Gate: Definition and 259 Discussions

A gate or gateway is a point of entry to or from a space enclosed by walls. The word derived from old Norse "gat" meaning road or path; But other terms includ yett and port. The concept originally referred to the gap or hole in the wall or fence, rather than a barrier which closed it. Gates may prevent or control the entry or exit of individuals, or they may be merely decorative. The moving part or parts of a gateway may be considered "doors", as they are fixed at one side whilst opening and closing like one.A gate may have a latch that can be raised and lowered to both open a gate or prevent it from swinging. Locks are also used on gates to increase the security. Larger gates can be used for a whole building, such as a castle or fortified town. Actual doors can also be considered gates when they are used to block entry as prevalent within a gatehouse. Today, many gate doors are opened by an automated gate operator.

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  1. H

    How can I connect a full bridge gate driver to an Arduino?

    http://www.infineon.com/dgdl/Infineon-IRS2453D-DS-v02_00-EN.pdf?fileId=5546d462533600a40153567ac42f2814 I currently have a H-Bridge circuit and would like to use the IRS2453DPbF to power it. I would like to do this using an Arduino but am unsure on how the Arduino connects up to the driver. It...
  2. nothing909

    Resistor value at the gate of a JFET

    Homework Statement Referring to the diagrams below, what would a suitable value for Rg and why? I have did a lot of research and can't get a clear answer, can someone clear it up for me?
  3. K

    What is the meaning of the arrow symbol on this gate valve schematic?

    I've come across a gate valve schematic symbol that I can't find any information on. It is the standard symbol with a small arrow pointing out from the side of it. I am working with an air system, and it uses two valves of this design according to the schematic. Can anyone tell me the specifics...
  4. C

    Designing a NAND Gate Logic Circuit

    Homework Statement Draw the logic circuit to represent the following Boolean expression using only NAND gates: Homework EquationsThe Attempt at a Solution Is this correct? Thanks
  5. Z

    2n3904/2n3906 driving mosfet gate

    I'm building a MOSFET driver like this. The signal source is 7V peak-to-peak. Vcc is 12V. The push-pull stage is 2n3904/2n3906.(datasheet http://www.kynix.com/uploadfiles/pdf8798/2N3904.pdf) I've tested the push-pull output before adding the transformer, and using a 50 ohm load, the output...
  6. N

    I Difference between measurement and passing through a gate

    My question is as follows, given a hermitian operator, what's the physical difference between performing a measurement on a particle to get an eigenvalue of said operator and acting on the state of the particle with said operator? What prompted my question is the swap gate used in quantum...
  7. P

    Finding the tension in a rope attached to a gate underwater.

    Homework Statement 2 & 3. The Attempt at a Solution I've worked out: The total force on the gate. I have worked out the centre of pressure which I got a value of 10/3m (from the hinge). For the moment about the hinge I got a value of 981,000Nm using the equation M=FN*X where X is the centre...
  8. moenste

    How can a NAND gate be used as a NOT gate?

    Homework Statement (a) The diagram represents a NAND gate with two inputs, T1 and T2, and an output X. Copy the truth table above and complete it. Show how a NAND gate can become a NOT gate. (b) Draw up a truth table for the combination of NAND gates shown above. 2. The attempt at a...
  9. moenste

    Simple Logic Gate Homework: Complete Truth Table

    Homework Statement Complete the truth table for the simple combination of logic gates shown above. 2. The attempt at a solution I think this should be correct, but just want to check, since I don't have a book answer to compare:
  10. C

    Implementing boolean functions with decoder and external gate

    Homework Statement Design an combinational circuit using a decoder and external gates defined by the boolean functions F1, F2, F3(see picture) Homework EquationsThe Attempt at a Solution I'm quite confused as to the exact method in doing this. I understand that a decoder takes n inputs and...
  11. G

    Hinge reactions from wind loading on gate

    Homework Statement Determine the forces at the 3 hinges of closed gate with a wind pressure of 700Pa on the gate. Mass of gate = 236kg wind pressure = 700Pa (apllied perpendicularly to the gate) gate dimensions: 4.1m high, 2.45m wide Distacnce from bottom of door to centre of hinges...
  12. T

    Electronic NOT gate chip question

    Hi, Can current flow both ways through a NOT gate, or is the diagram I saw, much like the picture I drew here, just drawn the wrong way around? Anyway, say it was correct, so what does this mean? Because the chip itself (the not gate chip Vcc = 5V and Gnd) takes 5V between it and the chip...
  13. T

    I How is a top gate used to change electron density?

    How is a top gate used to change electron density in 2D semi conductors? I get the principle, you are just shifting the chemical potential by some voltage so that there are more or less electrons in the specific bands. But how is it physically done? Thanks.
  14. F

    Why Does the Solution Use FH(6) Instead of FH(10) for Gate Force Calculation?

    Homework Statement the gate is 3m wide , is hinged at point A , and rests against a smooth wall at B . Calculate the force on the gate due to seawater pressure and horizontal force exerted by wall at B . I have attached the sample answer below . I don't understand why the author use FH(6 )...
  15. T

    Should Unused Inputs in a Quad 2 Input NOR Gate IC be Tied to Ground or Vcc?

    I have a quad 2 input NOR gate ic in which I am only using two of the four gates. I have read on the internet that unused inputs must be tied to ground. But if I tie these inputs to ground then I would get a one on the output. Will that draw excessive current ?, should I tie them to Vcc instead...
  16. T

    Linear and Angular Momentum on a wooden gate

    Homework Statement A uniform, 4.5-kg, square, solid wooden gate 1.5 m on each side hangs vertically from a frictionless pivot at the center of its upper edge. A 1.1-kg raven flying horizontally at 5.0m/s flies into this door at its center and bounces back at 2.0m/s in the opposite direction...
  17. P

    Simplifying output for a XOR gate using Boolean Algebra

    Homework Statement I'm trying to show that the output of this XOR circuit is ##F=A'B+AB'##, Homework Equations ##(A+B)'=A'\cdot B'## ##(A\cdot B)'=A'+B'## The Attempt at a Solution From the gates the output is ##[(A\cdot B)+(A+B)']'##, using De Morgan's laws this becomes ##[(A\cdot...
  18. T

    What is the maximum output current of a logic gate at 5V VCC?

    Hi, I have this logic gate http://www.ti.com/lit/ds/symlink/sn54hc32.pdf I am using 5V as my VCC. In the datasheet it says that the output current at 6V is 5.2mA. My question is, Is that the max current that it can output ?
  19. C

    Transistor Logic Gate : NOT Gate Explanation?

    Hi everyone. I would like to ask about this light sensor using not gate circuit. I use LDR as an input and a LED as an output. I have tried this circuit in Proteus, and it works. When the LDR 'off', LED turns on, and vice versa. But i don't really understand about the working principle of this...
  20. berkeman

    Does this gate construction look okay to you?

    I was helping with a disaster preparedness presentation at a local elementary school last night, and noticed this fence gate in front of the school. I'm not an ME, but it looks to me to have a small problem...?
  21. W

    Min force to open the water gate

    Homework Statement why Fr(Lp) = FB / 2 ? can someone help to explain ? Homework EquationsThe Attempt at a Solution shouldn't it be 2FB = Fr(Lp) ? since FB act on 2 sides of the gate ...[/B]
  22. Hassan Raafat

    How can I understand an OR gate with diodes?

    can i understand at OR gate with diodes , why o/p not equal the sum of two voltages (5+5=10v) , it's confusing me ?
  23. jdawg

    How Much Weight Is Needed to Keep the Water Gate Closed?

    Homework Statement A rectangular plate AB is 1.8 [m] wide and 2.0 [m] long. As shown below the plate is used to keep water (blue region) confined to the region. Find the weight of the gate necessary to keep the water enclosed. Assume the hinge at A is frictionless. Homework EquationsThe...
  24. D

    Shannon entropy of logic gate output.

    Homework Statement A particular logic gate takes two binary inputs A and B and has two binary outputs A' and B'. I won't reproduce the truth table. Suffice to say every combination of A and B is given. The output is produced by A' = \text{NOT} \ A and B' = \text{NOT} \ B . The input has...
  25. A

    Analysis of Train in Tunnel Problem Using an AND Gate

    This analysis uses an AND gate, the very embodiment of simultaneity, for clarity. A 1km long train travels through a 1km tunnel at a speed of 0.6c=180m/microsecond. At each end of the tunnel is a photo-electric beam sensor, which can be blocked by the train. They are connected to an AND gate...
  26. Salvador

    Mosfet gate charge with no voltage across D-S

    Hi , I would like to find out does a mosfet have any gate charge if there is no voltage applied across D-S or no ? my intuition tells me that there shouldn't be any gate chrge as there is no voltage on the " second plate" to attract that charge like would be the case in a capacitor, although...
  27. R

    Solving MOSFET Issues | 180 Ohm Resistor

    I am new to using MOSFET transistors as load switches. Here, I am trying to trigger the P-channel MOSFET to run a current through the 180 ohm resistor. I can not figure out what I am doing wrong. It is supposed to turn on for a small moment (at the zero-crossing moment of the AC phase), then...
  28. moenste

    Logic gates and truth table problems

    Homework Statement 2. The attempt at a solution Circuit: A B G D E F C 0 0 1 1 1 1 0 1 1 0 1 0 1 0 0 0 1 1 1 1 0 1 1 0 1 0 1 0Answer: Is (a) right? And any ideas what could be (b)?
  29. nmaganzini

    Is 70ps a Normal Propagation Delay for a 90nm Full Adder?

    Hi guys, I was just wondering, I'm designing a full adder for a bitslice of a 16 bit ALU. I have SPICED my design and I am getting a propagation delay for the AND mode between the two bits of about 70ps. I'm working in a low voltage 90nm process. Am I in the right ballpark in terms of...
  30. Domenico94

    CNOT Quantum Gate Schematics: Physical Implementation

    Hi everyone. I'm just looking for schematics of cnot quantum gate, but on the Internet it only talks about it from a mathematical point of view. I want to ask you if you have some drawing, or schematics of it, from a "Physical" implementation, in the sense, how are the spins prepared, how we...
  31. Aristotle

    Need clarification on Gate Delays & Diagrams

    Homework Statement This is just an example/solution to a timing diagram/gate delay for the circuit of logic gates. I am reading ahead of the chapter on gate delays & time diagrams, however, the book doesn't provide as much information. I am unsure how the solution came about in drawing their...
  32. S

    Metal Gate posts strengths & stresses?

    Hi folks, Just wondering if anyone can help with a few questions I have. I'm working on a design of a gate which, instead of using a traditional hinge system, will consist of an outer cylindrical post with the gate leaf welded directly onto it, and an inner cylindrical post which will bear the...
  33. O

    What Are the Noise Margins and Voltage Levels for CMOS Gates at 20 µA?

    Homework Statement 1)Determine the min acceptable values for VIH and VOH using VCC = 4.5 V and output current of 20 µA. 2)Determine the maximum acceptable values for VOL and VIL under the same test conditions. 3)Compute the noise margins. Homework Equations i=v/R The Attempt at a Solution...
  34. Y

    XAND Gate: Is it Real or Just a Rumor?

    I've been reading Code: The Hidden Langauge of Computer Hardware and Software by Charles Petzold, and he described the 5 basic gates (AND, OR, NAND, NOR, & XOR) with extreme clarity. In the chapter about adding machines, he described that we needed a gate that relays only when it receives a 0...
  35. M

    How to use Logic gate in Breadboard circuit?

    I am a High school student, I have read about Logic gates but when it comes to practical use I am confused. I am building a small project where I want to use OR and AND gate, but I don't know In which form they are available in the market, how to connect them on breadboard and how to power them...
  36. S

    Statics: tension in cable holding gate closed

    1. Homework Statement The tension in the cable is 800LBs. Find the depth of water that produces this tension. The gate is hinged at B; the cable is attached at A. (Figure 1)Homework EquationsThe Attempt at a Solution OK, so this is just 2 opposing lever arms: the tension in the cable is...
  37. S

    Can I Connect a Smaller Valve to a Varian M4 Diffusion Pump for Lower Costs?

    Hello all, I have a Varian M4 diffusion pump that has a 6 inch diameter opening at the top, is it okay for me to connect that to a reduced size opening like just 2 or 3 inches diameter so that I can use a smaller valve? I am only trying to pump down a cubic foot or two sized chamber. I am...
  38. A

    Torque & Force required to slide a gate

    Greetings all, I am trying to build a sliding gate operator. I have this wiper motor which says, 24v dc, 64rpm, nominal torque- 4Nm. Max weight of gate to be 400kg, sliding on a steel rail (Not sure how to consider rolling resistance or Co-eff of friction) . Max pull force to be achieved by...
  39. Metallican

    VRG (Vertical Replacement Gate) Mosfet

    Hello, Can someone please describe in a few words the idea behind the VRG Mosfet? Focusing on the Pros and Cons of the device. Thanks!
  40. perplexabot

    Input Resistance of Common Gate question....

    Hey all. I have been trying to calculate the input resistance of a common gate amplifier, but seem to have problems doing so. I know I have to set a test voltage (or test current) at the input, and I've been told, to ground the output. So using the Hybrid pi model for a mosfet, I did the...
  41. Freddythunder

    Can I make a gate that will work with AC voltage?

    Hello, I remember a few decades ago I built a circuit with my dad using what I think was a 741 op amp and a 555 timer and a loose wire. When you'd touch the wire, an LED would light. Then it took 30 seconds for the circuit to reset. I remember he said it was called a [logic] gate. Present...
  42. lvluffinz

    Need help obtaining hydrostatic forces on a gate

    I know we need to use F = pgA(h bar), as that's what I'm given in notes and whatnot, but I can't for the life of me get this simple one done. Any help would be GREATLY appreciated as I have an exam coming up on this.
  43. G

    Finding Torque for Angular Momentum Parking Gate

    Homework Statement Homework Equations Torque = r X F The Attempt at a Solution r is 2.5m since that's the length of the red (minus 0.5), and F should be the weight, so ma? That gives something like (5 * 2.5/3) * 9.8 * 2.5, which doesn't give me an answer at all :(
  44. T

    Gate drivers for IGBT inverter: How to isolate V supplies?

    This video describes my issue pretty well (I have it set to start when he talks about my specific situation): ETA: looks like the board doesn't allow the video to start at the specific time, the important stuff begins around 5:30 Our applications are a bit different as his design is for...
  45. A

    Design of Basic All-NAND Circuits using Logic Gate Technology

    The problem statement Hi I'm writing a report on a design of a basic all-NAND circuit. In reality, how are these circuits made ? Do we just use TTL etc. integrated circuits and combine them as necessary? Thanks
  46. Alxb577

    Difficult Logic Gate Puzzle Using Only 2 Input NAND Gates

    Homework Statement [/B] Impliment the expression which is already in minimum sum of products form using only two-input NAND gates. No gate may be used as a NOT. All inputs are available both uncomplemented and complemented. (The number of gates required is shown in parentheses.) f = ab'd' +...
  47. B

    Proving XOR Gate Universality: Elementary Operations & Logical Manipulation

    Hi guys, got a question that's got me stumped. Not looking for the answer as I'd prefer to work it out myself, just a nudge or a pointer in the right direction. I'm being asked to prove if an XOR gate can be classed as universal (like the NAND & NOR gates are), but not sure how to go about it. I...
  48. dwn

    Constructing a NAND Gate as Inverter: Troubleshooting Needed

    Homework Statement Constructing a NAND gate as an inverter. Homework EquationsThe Attempt at a Solution I've attached the image at my attempt to construct the circuit. The output is always on, which it should be except when both inputs are zero. Could someone explain what I am doing wrong...
  49. K

    Engineering XOR Gate Circuits: Draw Z with Lowest # of 2 Input Gates

    Z(A,B,C,D) = SUM-M(1,2,4,7,8,11,13,14) Draw circuit of Z with lowest number of 2 inputs xor-gates. Can i have a clue? I tried drawing k map and had too many terms.
  50. Feodalherren

    Fluid Mechanics: Hydrostatic Pressure on a gate with hinges

    Homework Statement Homework Equations Fluid Mechanics The Attempt at a Solution Lets start with the easy part: The pressure of the air is constant so the pressure will act as if it's a concentrated force on the center of gravity of the gate. F = PA = (10,000Pa)(.3)(.6)=1800N The moment...
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