Recent content by Braeden Hamson

  1. Braeden Hamson

    Very high current power supply

    I'm using a current shunt to measure the resistance, I omitted that from the drawing. It's above the FET though. And yes, the picture you show here above is correct in regards to the variable voltage. (With the red being negative of course) Is your suggestion to build a step down converter that...
  2. Braeden Hamson

    Very high current power supply

    I'm aware, however I have to do this testing for our FSAE electric vehicle. It's not optional. I understand the risks.
  3. Braeden Hamson

    Very high current power supply

    I am in the process of building a ~300A power supply with the intention of testing fuses at 300-70A over the course of 0.01 seconds to 60 seconds. So far I have an appropriate heatsink, 1 AWG conductors, and 300A capable contactor. I'm confident that all of my supporting elements are capable of...
  4. Braeden Hamson

    Recommendations for a battery and dc dc converter powered system

    I'm part of a student EV racing team. In my EV I have a regular 12V battery and a 300V - 12V dc dc converter. When the vehicle is first powered on, the 12V battery powers the systems long enough for the 300V supply to take over. In the past I've connected the output of the dc dc converter to...
  5. Braeden Hamson

    Audio Source Switching

    I did, it was all grounding issues. I connected the 12V ground to the analog ground, and I connected the digital ground to the analog ground in one place. I also added large electrolytic caps directly to the +/- of some of my noisy digital circuits. Now it's silent.
  6. Braeden Hamson

    Building a supply to regulate between 400A-100A

    I've got a bit of a bear of a problem to tackle. I need to determine the rating of in house fuses for my student racing team. This is an overcurrent protection fuse for a 21700 cell. The issue is that a the 21700 we're using can handle 45A and not really mind. This means the fuse for overcurrent...
  7. Braeden Hamson

    Audio Source Switching

    Its not white noise. It has a narrower frequency range, higher pitched generally. it sounds like very typical electronic audio noise.
  8. Braeden Hamson

    Audio Source Switching

    Hello, I've been having a pretty persistent problem switching between two audio sources, one is a generic bluetooth radio from amazon, the other is an Adafruit Soundboard FX https://www.adafruit.com/product/2220 I'm using a Maxim Integrated source selector chip...
  9. Braeden Hamson

    Op amp comparator troubles

    I'm comparing the analog position of a brake pedal to a set voltage, hence the need for a comparator. But I'm sure I could do this with a BJT. I'm always open to new ways of doing something.
  10. Braeden Hamson

    Op amp comparator troubles

    I'd prefer to do it that way. To be honest it's been a little while since I first made this circuit. I'm revisiting it as I need to fix it's issues. I can't remember why I did it this way. I think it's that else where in the circuit I need to know that the brake pedal isn't being pressed and...
  11. Braeden Hamson

    Op amp comparator troubles

    I've reconfigured the circuit based on all of your advice. I've added a pull up resistor, changed out the old mosfet for the BSS314PE which has a Vgs max of 20V. I changed the comparator's supply voltage to 12V. I don't have a great reason for this other than it will be slightly easier to get...
  12. Braeden Hamson

    Op amp comparator troubles

    That... Makes a lot of sense now. However it still doesn't work when I use a pull up to 12V. I think this is because the opamp is connected to 5V.
  13. Braeden Hamson

    Op amp comparator troubles

    Here's a PDF of the entire circuit. The circuit in question is connected to an external trailer brake light. Which in turn connects to the main IO header and is grounded there. The idea is to switch on or off power to the light.
  14. Braeden Hamson

    Op amp comparator troubles

    This is my complete circuit. (Everything that is relevant to this system.) I understand now that I'm lacking a pull up resistor. However I tried the circuit with a pull up resistor and the behavior was the same. I will keep trying
  15. Braeden Hamson

    Op amp comparator troubles

    Above is my circuit it used the LM2903 op amp https://www.mouser.com/datasheet/2/389/cd00000534-1795799.pdf One half of the chip is grounded and not used. The other is functioning as a comparator. The circuit should function as a brake light switch. Such that when the BSE_IN voltage is...
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