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  1. AnalogKid

    LEDs Parallel or Series

    The series-parallel approach in your schematic is the best way; stay with it. There are more complicated ways that would increase efficiency, but what you have is an excellent starting point. What is the value of the current limiting resistor in the LED strings? An input voltage surge...
  2. AnalogKid

    Seven segment upsize

    If you know the intended operating voltage and current of the large display segments, you can map the pinout with a power supply or battery and a resistor. Large displays often have multiple LEDs in series for each segment, so while the operating current probably is a fairly standard 10 to 20...
  3. AnalogKid

    Multi-input D flip-flop?

    Or a digital mux part like a 7464 AND-OR-Invert for the data inputs and a triple 3-in NOR to combine the clocks and invert both the clocks and data into a D FF. No matter how you approach this there will be some chance of a clock or data collision, unless that is mitigated by the true nature of...
  4. AnalogKid

    Multi-input D flip-flop?

    What is the width of the clock pulses? If narrow, as in they never overlap, then the clock signals also function as a mux control: One D FF. Three inputs into the three sections of a 4066 (or something faster), with the OR-ed output to the D input. The three clock signals enable the three...
  5. AnalogKid

    measuring LVDS signal

    If you want to see the two LVDS signals independently, you can do that with a high speed, low capacitance scope probe. Note that in some cases the signals are less than 0.5 Vpp and could be hundreds of MHz. If you want to see the logic state represented by the differential signal, or ah eye...
  6. AnalogKid

    Multi-input D flip-flop?

    Then you're back to three simple D ff's with an OR gate on the the output. You'll know that the output state is correct for whichever the latest clock came was, but you won't know which of the three inputs it is. ak
  7. AnalogKid

    Multi-input D flip-flop?

    The description in post #14 looks like one normal D ff with a 3-in or in the D input and a 3-in OR on the clock input. Most of the world's problems can be solved with a CPLD, but that's overkill for this. ak
  8. AnalogKid

    Multi-input D flip-flop?

    If you think through your description, you'll see that it is not complete. Either that or it is simply a single ff and some OR gates. ak
  9. AnalogKid

    Multi-input D flip-flop?

    I think I know what you are asking about. For a long time I've wished for a chip like a quad logic gate that had four independent, stripped-down D flipflops in one 14 pin package: 4 D inputs, 4 clock inputs, 4 Q outputs. A 74LS279 comes close as a quad S-R. ak
  10. AnalogKid

    using control voltage from synthesizer to manipulate VGA signals

    Depends on what you mean by "visualization." Most monitors will not come on until they see valid sync signals, so you would have to get those from a computer VGA port. This is what the tutorial means by hacking the cable. If you want anything other than full screen flat colors, like the...
  11. AnalogKid

    Coil replacement

    The economics of large-volume manufacturing are working against you. While it can cost thousands of dollars to have a manufacturer create a custom or modified-standard version of something as simple as an inductor, the custom part might reduce the overall cost of the circuit, and saving only a...
  12. AnalogKid

    Seven segment upsize

    The future Kit website has the schematic, board layout, and pinout of the intended display. Note that the board is set up to use either common-anode or common-cathode displays with a jumper, a nice feature. If you have the pinout of your large displays, you can match the segments one-to-one. ak
  13. AnalogKid

    Charging coin cell battery and feeding the board circuit at the same time

    Your overall plan looks good. The TPS datasheet should have some transient response information or plots. Another approach is to eliminate both diodes and connect the battery charger directly to the battery, which is connected directly to the TPS. This only works is the battery charger has...
  14. AnalogKid

    Breathing LED Lamp - Need Help!

    Breathe? ak
  15. AnalogKid

    Self regulating ramped voltage oscillator?

    Why? ak
  16. AnalogKid

    LM350T variable voltage regulator

    Not without your actual schematic. Too many variables. OBTW, you will be moving over 15 W in the device. Heatsink? ak
  17. AnalogKid

    Why does the current always remain the same in a series circuit?

    I'm not picking on you, but your example makes absolutely no sense because in a series circuit there is nothing to "assume." I don't know what a "bit voltage drop" is, but if you meant big voltage drop, that is not something you can just assume when analyzing a series circuit. ever. ak
  18. AnalogKid

    Hand Sanitiser Dispenser Circuit

    You could contact xxx Wave Technologies (name on the pcb) to wee if the want to help. A small change to the PIC firmware will do what you want. ak
  19. AnalogKid

    Need help delaying a voltage feed for about 150ms to 300ms.

    This forum is not an on-demand service bureau. Your last two posts are fewer than 22 hours apart. You might ant to adjust your expectations just a bit. At its core a delay circuit needs a timing part and a switching part. ADI, Maxim and others make uP reset parts that have 140 ms delay times...
  20. AnalogKid

    Microphone Input to Square Wave

    I know, and I like it. It is good to review from time to time things that "everybody knows". In this case, it comes down to what is meant by the word "alternating". Varying amplitude of the EM field(s)? Varying direction of electron movement? I think the fact that the term is alternating...
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