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    toggle between GND & 5v?

    qweets, I'm sorry, I didn't understand about the power supply. So the controller and CMOS logic are all running off +5V. You should be able to connect the the logic lines directly. Even the 4013 reset. If you want the 4013 array to be reset at power-up, adding a resistor to + 5...
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    toggle between GND & 5v?

    qweets, So the 4013 Vdd supply is +12V? Then all of the Arduino pins controlling the 4013s require level shifting. The MC14504 is a CMOS hex level shifter. That would do for the reset, as well. Next time you do this, consider: If you are using transistor LED drivers, and have 16...
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    LED driver chip question

    steveeeee, CocaCola is correct. No separate resistor or other voltage dropper is needed on each LED. Your driver IC does the work. It actually regulates the current for each LED. There might be some advantage in setting the LED supply voltage to an optimum value different from +5V. If...
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    toggle between GND & 5v?

    qweets, You have not mentioned what controller IC you are using, but generally, a single I/O pin will be able to drive 64 CMOS inputs. If you need more speed, you can parallel multiple I/O pins. ( There is no requirement for speed on the 4013 reset pin.) Does the processor use...
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    toggle between GND & 5v?

    CocaCola, > max sink/source of single micro is far below that of multiple 4013s. Surely you are not supposing that the OP is paralleling multiple 4013 outputs to get more current drive capability? It would make more sense to parallel processor I/O pins, as fewer pins would provide...
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    toggle between GND & 5v?

    qweets, You should consider dispensing with all of your 4013s and just using more microcontroller I/O pins. If you require lots outputs, you can use multiple microcontrollers. BTW, how many are "lots"? Ted
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    Pulse Transformers

    Chris, If you really need 2A @ 200V, that's 400W. The pulse transformer you mentioned is no doubt much too small for this power, and it lacks agency approval for this application. A SMPS running off the mains is not a trivial design challenge. You can get a good idea about what's...
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    Op-Amp premature clipping

    Phone? Is that a 600 ohm device? What are you connecting to your input? You want something with a fairly high output impedance to feed your current input. Don't try to feed a voltage in there. Try reducing the signal level and see if the distortion decreases at some point. You need an...
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    Heat Issues with LM732 Power Supply

    What's an LM732? Are you sure you are not making an FM radio? ( uA723 and uA732 are Fairchild numbers; I don't think National ever made the '732.) Could you possibly have some digits swapped in the part number? A linear supply is big, heavy and inefficient, but can be more...
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    Op-Amp premature clipping

    boogyman19946, Several comments about the schematic you posted: I wonder what the device labeled "SP" might be. If this is a high impedance headphone, the circuit may work to some degree. If it is a 4 ohm sub woofer, not so much. The impedance and the power requirements are the...
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    What does this mean by isolated?

    selanac, "Elmer" is a ham radio term for mentor. You know, the old guy across the street who tinkers with radios in his basement, and is willing to take some time to help the neophyte. blis, I'm sure someone around Glasgow would fit this description. Look for the nearest RSGB...
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    using SIPO LED driver with PIC controller

    steveeeee, The ULN2003 is not really what you want. Each output can pull down only; it's just an NPN darlington. And they are slow. A single PIC I/O pin may be able to drive all 49 inputs. The MBI5026 is a CMOS device, though the LE terminal has a weak pull-down. 250k ohm / 49 =...
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    .4 V DC to 5 V DC possible?

    zach48191, I understand that you are still learning this stuff. The problem is really analog in nature, and quite beyond what you learn in basic digital electronics. The linked circuit and LM3914 present a fairly complex nut to crack. The LED driver outputs are constant current sinks...
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    .4 V DC to 5 V DC possible?

    zach48191, Thanks for providing some more hints about what you are doing. There are still outstanding questions, though. And a new one: Do you really want the heater to go off only over a narrow temperature range? If the LM3914 is in dot display mode, the heater will go back on if the...
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    Can somebody explain this simple circuit please?

    Yes, the capacitor might get a little reverse voltage. This might not be the best thing you could do to the capacitor. But, if this is just an experiment on a breadboard, nothing bad will happen before you get tired of staring at the blinking lights. In fact, I suspect the cap may never...
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    output power against load

    Nayia, This is a complex subject. I would not hurt for you to tell us more about what you are doing. Practical answers depend in part on things like the frequencies involved, the power, any devices you expect to use, and no doubt something important I didn't think to ask about. Yeah...
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    doubt regarding yaw rate circuit in abs/esp

    > could someone expain how the circuit works? > (yaw rate sensor (and lateral acceleration sensor) measures the rotational acceleration of a > vehicle along the vertical axis.) The diagram shows an input network followed by a Sallen-Key low pass filter. Presumably some sort of...
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    What does this mean by isolated?

    blis, There is no telling what the vendor means. There is no absolutely standard technical meaning of the word, and English is not the vendor's first language. There may be a capacitor in series with the hot side to isolate the counter circuit from DC on the input. There might be two...
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    .4 V DC to 5 V DC possible?

    zach48191, So all of my stated assumptions are correct? I had a bunch of questions for you that still lack answers. I'm trying to avoid a long succession of suggestions each of which you counter by "I have no PNP transistors", or, "In Bagdad we can get only 5V relays with 10 ohm coils"...
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    .4 V DC to 5 V DC possible?

    zach48191, OK, sounds as if we may now understand what you are doing. Starting with the linked circuit, you want to take the LED driver outputs from the LM3914, and use one or more to make the relay go on and off. The linked circuit will have only a small output swing at each...
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