1. fablau

    Why did this zener diode explode?

    Hello everyone. Please, help me to understand why D1 of the circuit below exploded when I increased the voltage to 32v. Everything was working perfectly at 22V, then I increased the voltage to 32v and D1 exploded. As you can see from the schematics, that diode drives nine N-Channel MOSFETS when...
  2. jm_sanz

    Estimating junction temperature from top case of SMD MOSFET

    Good afternoon to everybody. First post over here! :D I am working on the estimation of junction temperature from top case temperature measurement. I have seen that manufacturers avoid the characterizing the molding this resistance which is crutial for this purpose. From now on I will take...
  3. JesusLopez

    PID Controlled Peltier Heating and Cooling

    My goal is to rewire a Peltier AC unit by removing the on-board PSU and Analog temperature controller. I would like to convert the AC unit to Cool and Heat by reversing the Peltier modules polarity. Then control both heating and cooling functions with a PID. Then running it all with an external...
  4. DanDare

    Flyback diode problem (heat) in boost converter

    Hello! I need to decide what I should understand/learn to go ahead with my boost converter and stop killing my MOSFETS in the wild. I'm not a engineer (at least not one of the 'right type') and electronics is just a hobby. I have a boost converter that's basically scheme.jpg (MOSFETS are...
  5. T

    Optocoupler Input switch problem

    I am having a problem switching the positive input of an optocoupler to ground using a mosfet. Please look at the schematic and plots I did. The mosfet gate is getting 5V, but the output attached to the 1.5K input resistor doesn't go to 0V?
  6. O

    How Can I measure MOSFET ro(output resistance), ID(DC current) at LTSpice?

    Viewed 1 time 0 The subject is to make ro=500k, ID=100u by setting VG3,VG4 and W/L of MOSFET. And I got the exact values from Hand-calculation, and am trying to test it by using LTSpice. I did make this schematic. and DC currents of two mosfet was around 74uA (I don't know it is right way to...
  7. crookedspoon

    Blinkers as positioning lights, circuit fails on high(er) load.

    Hi all, First post here and very much beginner in electronics, trying to dive in. For my motorcycle, I’m trying to implement positioning lights in the blinkers: When turning on the blinkers, the blinker blinks regularly. When the blinkers is turned off, after a short delay, the blinkers shine...
  8. A

    A few questions regarding Mosfets

    Hi. I was reading the Microelectronic Circuits be Sedra/Smith and I have some questions on Mosfets. I will ask the questions one at a time. On 4.1.3 Creating a Channel for Current Flow "Consider next the situation depicted in Fig. 4.2. Here we have grounded the source and the drain and applied...
  9. J

    Having problems trying to get a high side switch to work 3V switching on 5V

    The context of my project is I am using an ESP-01 as a "smaller" circuit that is deep-sleep capable, running off a coin cell. It turns on a larger MCU with its own battery pack and runs at a higher voltage. Both work together regarding data transmission. The first time I made this thing, it was...
  10. Lawrence White

    Struggling to get this MC33035 to work, can anyone help at all?

    Afternoon everyone, Getting rather frustated with somethign that seems straightforward to me... I have researched and corrected any mistakes I have made, done a rebuild several times, but can never get this thing to work. draws about 10mA on a 12V test voltage and thats it. nothing seems to...
  11. farzad latifeh

    MOSFET ohmic region, needs to be explained

    Can anyone explain to me how to understand the ohmic region of a MOSFET from its datasheet, or any formula to calculate the ohmic region according to the MOSFET datasheet, let's say IRFZ44n vs IRF3710, which one has a bigger ohmic region and how to analyze them accordingly? I am not an expert...
  12. U

    Question about inductive spiking

    I'm working on building an electric scooter and yesterday the speed controller had a MOSFET failure that I suspect was caused by inductive spiking. This was very surprising to me because I had a schottky diode in parallel with the motor to prevent this type of failure. I took the speed...
  13. I

    MC2100 Rev B - Issues (Treadmill Main Board)

    MC2100 RevB- I have aquired 3 of these boards (dang Proform) over time and now at a stage that all 3 have their own weird issues. I tried replacing MOSFET IR260N on two of the boards in hopes of fixing it, as I don't have a bench setup to diagnose exactly what could be the issue, I have switched...
  14. KaputFPV

    Mosfet array for low voltage and low current

    (I am quite new to electronics and pcb design.) (necessary files are attached, tell me if you need something else ) ------------------------------------------------------------------------------------------------------------------------------------------- Hi everyone, I am making a MOSFET...
  15. E

    MOSFET gate , offset PWM questions

    Hello! A little about me , i haven't formally studied electronics, i do not own or have access to an oscilloscope. I have been researching about MOSFETs to use an IRLZ44N as a switch in a basic boost converter, on the IRLZ44N datasheet Vgs(th) = 1v to 2v, as i undertand this Vgs(th) is the V...
  16. M

    Who Knows MOSFETs - Can Noise be Reduced? (Dimmer circuit)

    Hi, I created the following circuit here. The DIM Control Pin sources a 10uA current. I am getting 0.5V of noise on that pin (looking at the oscilloscope). It probably has to do with the GNDA being connected to the MOSFETs. And probably to do with my PCB layout. Currently, I don't have...
  17. E

    Chaos generator MOSFET, how does it work?

    The circuit in the picture is a chaotic generator formed from MOSFETs as opposed to op amps from the usual chaos generators. How does it all work exactly? Whilst I have knowledge of how MOSFETs work and such, the connections etc are hard to understand what they all do completely. In-depth...
  18. F

    What Dual Gate MOSFET for small signal RF Amplifier circuit in HF band... & where to buy?

    Looking at HF receiver schematics on line I see many use Dual Gate MOSFET's as the first amplifier stage... and also for the mixer... mixing the incoming RF signal with the local oscillator. However all of the MOSFET's I've checked out seem to be out of production... and the ones I've found...
  19. W

    MOSFET allows current through even when turned off

    Hi, I'm relatively new to circuit design and I'm trying to create a circuit to turn on/off a 6V DC motor using a microcontroller. To do this, I am using an N-channel MOSFET. The MOSFET appears to be working, because the drain to source resistance when the gate = 0V is ~10 MΩ, and when the gate...
  20. F

    PMOS on Zeta Converter

    Hi, I'm studying the Zeta Converter topology for Photovoltaic Applications. In every documents, it is specified that the switch is PMOS. I don't understand why a PMOS is needed. Which are its advantages? Being a switch, is it possible to use an NMOS instead of PMOS? Obviously, an isolated...
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