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  1. BobK

    PWM voltage divider

    PWM does not end up with a stable voltage, it is changing constantly. If you are reading the voltage, for instance with an A/D, you would get erratic readings. PWM with a low pass filter can put out a stable voltage. What is consuming the LOAD OUT signal? A digital potentiometer does...
  2. BobK

    PWM voltage divider

    Okay. That will not work. The output would be a voltage that varies between the max and some other voltage at the PWM frequency. An digital potentiometer would be a better solution. Bob
  3. BobK

    PWM voltage divider

    Hi mj, and welcome to the forum. A voltage divider is not a a circuit you use to power a load. The load will affect the voltage of the divider, a varying load will make the voltage delivered vary, which is usually not the desired effect. Depending on the type of the load you are using...
  4. BobK

    High Voltage Regulator Circuit Help

    500MA at 250V is 125 Gigawatts (pronounced Jigawatts)! Doc Brown
  5. BobK

    Pulsated LD

    Electro, Are you so embarrassed about the nature of your project that you do not wish to disclose it, or do you think you have invented earth shattering technology and want to keep it secret? In either case, we cannot help with the cryptic descriptions you keep giving. Bob
  6. BobK

    Op Amps: Unwanted Oscillations

    I have not had that problem. Can you post the circuit? Normally, a 1uF decoupling capacitor will do. Bob
  7. BobK

    Convert V to mV

    Enough of this nonsense. How about telling us what it is you are trying to do? And I don't mean transmitting a -70mV signal over 10km. That makes no sense. What is the ultimate goal of your efforts? Bob
  8. BobK

    Leds and drivers?

    There is a lot of info about driving LEDs here; https://www.electronicspoint.com/got-question-driving-leds-t256849.html Bob
  9. BobK

    Convert V to mV

    Could you post a link so we can see whether it is nonsense or you are just misinterpreting it? Bob
  10. BobK

    Could use some help selecting a graphics/tft board with PIC micro controller

    Did you look at the amount of RAM on the 8-bit microcontroller? I think you will find it insufficient to handle a graphics screen. Bop
  11. BobK

    Convert V to mV

    Yep, I did that. It was based on an actual cartoon of the same name that I saw at an animation festival. Bob
  12. BobK

    Convert V to mV

    How about telling us what you want to do with he 80mV? Bob
  13. BobK

    Convert V to mV

    But that would be cruel and unwarranted. When the first guy used ASCII art, there were only fixed width fonts. It is the proportioanal fonts that screwed it up. By the way, I was one of the creators of the classic ASCII animation of Bambi vs. Godzilla. Bob
  14. BobK

    Short burst voltage problem

    Great, always good to hear about a success. Bob
  15. BobK

    Short burst voltage problem

    A bipolar transistor would not work well, since it will always have a voltage drop from C to E of a couple of hundred millivolts. A MOSFET would not have this problem. Bob
  16. BobK

    Schematic diagrams with antiparallel diodes

    It limits the voltage to about + or -0.6V Bob
  17. BobK

    Low-current batteries?

    The USB standard is 4.75 to 5.25V. The batteries, when fully charged are unlikely to produce more than that when any significant current is drawn. I think they would be safe to use with no regulator. Bob
  18. BobK

    Short burst voltage problem

    If I understand what you want correctly, this should work. Use a MOSFET between the center of the trim pot and the 1.6V side. When the MOSFET is on, the output becomes 1.6V, when off it is whatever the trim pot is set to. Bob
  19. BobK

    Low-current batteries?

    If a NiMH battery gets too hot it vents and loses capacity or even dies. If it is getting too hot to touch, you are in the danger zone. You realize that two NiMH batteries is only 2.4V and go get 5V out at 500mA, you will need over an amp from them? I would use 4 NiMH and forget the boost...
  20. BobK

    A Simpler Solar Charger Question (I hope)

    Then just buy some shottky diodes as originally suggested. Bob
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