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  1. crutschow

    Circuit Simulation of LTC3703

    It is not. You still are having problems with LEDs. You placed an LED (D5) across R6, part of the voltage divider that provides feedback that determines the output voltage. Since the FB reference voltage is only 800mV, the LED will never light. If it did, it would cause an incorrect output...
  2. crutschow

    Timing circuit using LM339

    You have a feedback load on U2A of 15kΩ so a 10meg pull-up resistor will only give a small output voltage. You need a smaller pull-up resistor to get a significant voltage out. Putting random component values into a circuit seldom gives good results.
  3. crutschow

    Testing Current of AC-to-DC converter module without load

    To provide a 1A load at 12V requires a 12Ω power resistor. The resistor will dissipate 12W so you should get a 12Ω, 20W resistor. If its metal-case resistor with mounting tabs, then it will need to be on a heat-sink. If it's a ceramic/cement type than it doesn't need a sink.
  4. crutschow

    Timing circuit using LM339

    The LM339 has an open transistor collector output so needs a pull-up resistor on its output, as Alec_t noted.
  5. crutschow

    Circuit Simulation of LTC3703

    But that bias is powered from the output voltage, so it's no different than one on the output.\ According to Ohm's law, to put 10 amps through a 1k resistor requires 10,000 volts. Do you not understand what I mean by saying you should put them from the voltage being monitored to ground?
  6. crutschow

    Circuit Simulation of LTC3703

    Not surprising the circuit doesn't work. The LEDs go from the input and output voltages to ground, not in series. And why did you put one in the Vcc bias line? You are trying to disobey Ohm's law. How do you expect amps of load current to go through the 1kΩ resistor and LED? Only the upper...
  7. crutschow

    Add one resistor to give bipolar LM555 oscillator a 50:50 duty cycle

    The problem with written communication is that you don't hear the voice inflections or see the expression of the other person conveying the message, so its intent is sometimes misinterpreted.
  8. crutschow

    Circuit Simulation of LTC3703

    Note that for a 100V input, you will need a higher voltage rated MOSFET (at least 120V). Also Q1 will need to be mounted on a heat-sink.
  9. crutschow

    Circuit Simulation of LTC3703

    Because the Vcc and DRVcc bias voltages are limited to 15V max., so with a 24V-100V input, some means is needed to reduce the voltage for those inputs. This requires either a separate supply or the Zener-Transistor kickstart circuit shown, to provide Vcc until the output can supply the Vcc voltage.
  10. crutschow

    Circuit Simulation of LTC3703

    Here's the simulation with 24V input, 10A load, and Vcc generated from the output 12V. The simplified circuits you posted are just to indicate the basic circuit configuration, not to build an operating circuit. The series resistor values for an LED are: (Vs-Vd) / Id, where Vs is the supply...
  11. crutschow

    Circuit Simulation of LTC3703

    What is Vin?
  12. crutschow

    Add one resistor to give bipolar LM555 oscillator a 50:50 duty cycle

    Yes, I misunderstood your comments about simulators. I'm used to having the models (and my results) be fairly accurate, so I was lulled into a false sense of security and wasn't sufficiently critical of my results with that old 555 model. I appreciate you noticing the error. As far as time...
  13. crutschow

    Add one resistor to give bipolar LM555 oscillator a 50:50 duty cycle

    I never used any of those straw-man words, so why did you put them in quotes? Who are you quoting besides yourself? I was using an old 555 model that doesn't model the nominal trigger points accurately. Below is the simulation with a better model which uses the nominal trigger points, and does...
  14. crutschow

    Add one resistor to give bipolar LM555 oscillator a 50:50 duty cycle

    Here's the simulation. The duty-cycle is not close to 50%. I trust the simulation, so I think Figure 14 is in error. Having fun yet? Better yet, for even more fun you should learn to do you own simulations with LTspice, so I don't need to be the middle-man.:rolleyes:
  15. crutschow

    Building a manually-controlled touch screen tapper for controlling farm tractor GPS

    The LM317 uses feedback from the output to maintain a constant output voltage, independent of the input voltage and output current. It adjusts the output voltage to maintain 1.25V across R2 (between the OUT and REF terminals). For the circuit below, this generates a current of 1.25V /121Ω =...
  16. crutschow

    Add one resistor to give bipolar LM555 oscillator a 50:50 duty cycle

    Whose fun? That would make the discharge level close to the THRS trip point and make the high period very long. It's not something one would do in a real circuit, so see no reason to simulate that.
  17. crutschow

    Building a manually-controlled touch screen tapper for controlling farm tractor GPS

    A buck regulator is a switching type regulator to get high conversion efficiency (>80%). A 12V to 2V converter would only be about 15% efficient (the rest generating heat). On what basis do you think it needs near 3A? Did you measure the current? Since I assume this current is only for a short...
  18. crutschow

    Circuit Simulation of LTC3703

    You right-click on the model icon and it will show you the path to the test fixture example (below):
  19. crutschow

    How to calculate my battery bank Ah ,kw and Kwh

    In your calculation you had Ah as one of the factors, so that calculates to be Wh.
  20. crutschow

    How to calculate my battery bank Ah ,kw and Kwh

    I believe that's Wh.
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