1. Luiz Fernando Vieira

    What is the dielectric value of the mosfet gate when hiring acceptors?

    Hello, I'm having trouble finding the value of the right concentrators that are on the gate of the gate (SiO2 as gate dielectric and P-type substrate [NA=?]) Could someone indicate a material to show a usual value?
  2. MrsssSu

    74HCT library file LT Spice

    Hi all, does anyone have the 74HCT.lib with the square symbol of 74HCT.lib :)? Do you mind sharing it because I am having a hard time googling the one with a square symbol as shown above? Thank you and appreciate it :)
  3. MrsssSu

    Rain Drop Led

    Above is quoted from here. This circuit produces beautiful rain drop led. May I know how do I actually increase the deadtime which means all led are off for a longer period for all the 4 led as shown above? My LT Spice file is below. Thank you :)
  4. MrsssSu

    Add symmetrical deadtime in PWM

    The above is quoted from here and I have build the circuit in LT Spice for simulation. The output (highlighted in pink) is as expected that is complementary PWM. However, the question is how do I actually position the wave so that it has same amount of dead time between both waves because it...
  5. MrsssSu

    Increases deadtime in IR2184 IC

    This LT Spice circuit is recreated from the IR2184 datasheet on how to make a complementary PWM signal with dead time. However, the problem I am facing now is the PWM fed into the 2 mosfets as shown in the diagram above, the dead time between the 2 signals does not increase even if I increase...
  6. MrsssSu

    Delay Timer using NE 555 circuit

    Hi all, :) I am trying to simulate a circuit at https://elonics.org/adjustable-auto-on-off-delay-timer-circuit-using-555/ for delay timer in NE 555. I have replaced the switch with a mosfet, however I don't get the correct output :). I have attached my LT Spice file below. I am not sure what I...
  7. MrsssSu

    Measure Earth Magnetic Field using Hall Effect

    Hi all :), This is about Hall Effect from here. The voltage across a metal will change based on the strength of the magnetic field. I am wondering whether this will be accurate in reading small magnetic field such as the earth's magnetic field to point to the NORTH. From my knowledge, since the...
  8. MrsssSu

    Discrete Half-bridge driver

    Hi readers:), I found datasheet for HALF-BRIDGE DRIVER IC here . I was hoping to find the IC discrete components circuit from which it was built upon using transistors, diodes, resistor only but its not in the datasheet. I tried to search the web for it but it offers H-bridge with negative and...
  9. MrsssSu

    IR2184 gate driver LT spice file

    Hi all, can anyone share IR2184 gate driver LT spice file with me that can be downloaded ? Thank you:)
  10. MrsssSu

    Small pull-down resistor for mosfet (fast switching, high capacitance)

    Hi readers, When I used this IRF 3205 which has high capacitance between the Gate-Source of the mosfet, whenever I add a lower pull-down resistor, the switching becomes faster and faster (visible nice square wave). For my case, for IRF 3205 to fast switching at 20kHz (nice square wave), it would...
  11. MrsssSu

    PS2501 optocoupler LT Spice Library File

    Hi, is there anyone having this PS 2501 optocoupler library from LT Spice. Pardon Me, I couldn't find on the internet :). Please attach it below. Thank you
  12. A

    Finding the gain expression for this CMOS operational transconductance amplifier

    So here's the circuit: I think M2 is a common source amplifier and M4 a common gate amplifier, so they form a cascode amplifier where the gain is given by : Av = -gm2 * r0, r0 is the impedance at the node where the drain of the common gate amplifier is at (Vop). r0 = ( [rds8 // (rds2a * (...
  13. MrsssSu

    PNP and NPN recommendation for mosfet driver

    Dear readers, Above is taken from here . Can anyone recommend transistor Q1 (npn) and Q2 (pnp) to me for driving a mosfet at a 100kHz or higher. What are some of the common best fast switching Q1 and Q2 that can handle high current and high frequency PWM at its base ? Thank you :)
  14. MrsssSu

    Optocoupler for high frequency

    Dear Readers, I got this PS2501 optocoupler datasheet at here. In the image shown, the rise time and fall time is microseconds and I am afraid it's not suited for my needs as it will produce some switching losses in H-bridge circuit running at 100kHz minimum. Are there any very-high speed...
  15. MrsssSu

    NE 555 (On , Off, ON) when subjected to different input voltage

    Hi readers, :) I found this at Click here This is an example of a disconnect and reconnect circuit using NE555. This means that the state of load will be (High, then, Low, them High). However, when I simulated using LT Spice it just give me (Low and High only). Does anyone know how to make the...
  16. MrsssSu

    Produce an oscillating Dc wave

    Hi People :), The reason why I will be needing an oscillating dc waveform is because I need it to be fed into the input of a comparator to produce high frequency square wave dc signal. I built this Wein Bridge Oscillator and it works fine to produce quite a high frequency sine wave. However, I...
  17. MrsssSu

    Produce high frequency square wave

    Hi readers:), When decreasing R1 value, output frequency will increase. However, I get bad waveform when high frequency. How do I get a good square wave (100kHz) using this LM 741 chip that I bought? Simulation is attached below for your reference and modification to the answer :)
  18. MrsssSu

    Generate Complementary PWM with dead time.

    I have a similar question to click here. However, in my case i am using ne 555 for logic gate inverter :). I have generated the complementary PWM and it works totally fine. My question is how to add a dead time between the pulses. From click here, people suggests to use an RC network, how do I...
  19. MrsssSu

    Is this part a tiny step-up converter?

    Hi People :), This is a design I saw at here. Does this highlighted part a tiny step-up voltage converter after it has been stepped down by the transformer in order to prevent voltage drop when a heavy load is connected? Thank you
  20. MrsssSu

    High current Step-down converter efficiency problem

    Hi People:), I am trying to build a synchronous step-down converter but my LT spice simulation shows poor efficiency. The picture above is at Here . I have attached my LT spice below for reference. May I know if this is the right way or anyone can correct my LT spice file and send it in the...