Electronics design ideas 2019

Innovation is critical in today’s engineering world and it demands technical knowledge and the highest level of creativity. Seeing compact articles that solve design problems or display innovative ways to accomplish design tasks can help to fuel your electronics creativity.

You can find many very circuit ideas at ePanorama.net circuits page.

In addition to this links to interesting electronics design related articles worth to check out can be posted to the comments section.






  1. Tomi Engdahl says:

    Where To Connect the Outside Foil on Capacitors

    Some non-electrolytic capacitors have a banded end, occasionally labeled “outside foil”. These capacitors are typically made by taking a long narrow strip of insulating material and placing a strip of metal foil on both sides of it. The two pieces of foil become the plates of the capacitor, and the insulator is the dielectric. This long strip is then wound into a cylindrical shape, leads are attached to the two foils, and the entire assembly is then potted in some type of material designed to keep moisture out of the capacitor and to keep the capacitor mechanically stable. Since the capacitor is wound into a cylindrical shape, one of the foil sides is on the outside, and the other is on the inside. The outside foil terminal connection is then marked with a band to indicate the outer foil position.

    In order to take advantage of the shielding properties of the outside foil, the capacitor must be connected in the circuit in a particular orientation.
    Where to connect the outside foil?

    The proper way to connect the outside foil is to the low impedance side of the circuit, which, in the case of coupling caps, will normally be the plate of the previous stage. If it is a bypass cap to ground, connect the outside foil to the grounded side. If it is a bypass cap from a signal to B+, connect the outside foil to B+. The outside foil will act as a shield against electric field coupling into the capacitor, so you want it to have the lowest impedance return path to ground.
    For AC signals, the power supply rail is effectively at ground potential, just as the ground rail is. This is why it makes a good point to use as a shield ground.

    , it is sometimes a good idea to bypass electrolytic capacitors with a smaller value foil or other type capacitor.
    I have seen where a well-known guitar amplifier “guru” said to connect the banded end to the grid of the next stage because it is at ground potential. This is completely wrong, because the grid circuit is a very high impedance point in the circuit. The grid of the tube itself is very high impedance, and it is usually shunted by a high resistance of 220K to 1Meg, and also usually has a large series resistance as an interstage attenuator as well. Because of this, it would make a very poor choice for electrostatic shielding. The plate, on the other hand, has an impedance equal to the internal plate resistance of the tube in parallel with the plate resistor (assuming the cathode is bypassed), which for a typical 12AX7 is around 38K total. If the cathode resistor is unbypassed, the output impedance is a bit higher, around 68K or so, depending on the value of the cathode resistor, but still well below the input impedance of the next stage. Tubes with lower internal plate resistances, such as the 12AT7, will have even lower output impedances.

    What if the capacitor doesn’t have a banded end?

    This marking of the outside foil was very common in the “good ol’ days” of electronics, but, sadly, most capacitor manufacturers nowadays do not bother to mark the outside foil, so we’re left to fend for ourselves. If the capacitor has no banded end, the outside foil connection could be on either end, so there is no easy visual method to determine the best orientation of the capacitor. However, if you have access to an oscilloscope, you can do a simple test to determine which is the outside foil terminal.

    Set the scope up to the most sensitive vertical scale (20mV or less, preferably) and connect the scope probe across the capacitor (ground to one side of the cap, probe tip to the other). Grab the capacitor tightly with your fingers, and note the amplitude of the induced 60Hz AC signal (or 50Hz if you are on the other side of the pond). While still holding the capacitor tightly, reverse the scope leads and you should see a dramatic difference in the amplitude of the induced AC signal. The orientation with the lowest induced signal is the one you want, and the ground lead of the scope is connected to the outside foil in that position. Mark it, and connect that side of the cap to the lowest impedance point in the circuit, typically the driving source plate when used as a coupling cap, or the grounded end if used in a shunt position. If you cannot see a large enough induced AC signal by holding the capacitor between your fingers, place the capacitor on top of an AC line cord

  2. Tomi Engdahl says:

    For example, the maximum gate voltage for a typical MOSFET is usually between 5 and 10V while IGBT require 10 to 12V and a SiC device’s maximum gate voltage is typically 18 to 22V. In addition to their different gate input voltage ranges, all these devices require that their high-voltage and low-voltage circuit paths must be isolated from the ground to prevent unwanted stray currents that could pose a hazard to both the product and its users

  3. Tomi Engdahl says:

    Make a Joule Thief

    Yes, it’s the infamous Joule Thief, in Instructable form! For those of you who don’t know, the Joule Thief is a tiny little circuit that allows you to drive a white or blue LED from voltages as low as 0.5 volts. You think those batteries are dead? Don’t throw them out yet! Hook them up to the Joule Thief to squeeze every last drop of energy out of them!


  4. Tomi Engdahl says:


    The joule thief is a blocking oscillator used as a boost converter. The normal output is a series of current pulses, but a diode and a capacitor can turn this into a steady DC voltage. This voltage is highly load-dependent however, so a MOSFET can be used as feedback to turn off the oscillator when the output reaches its threshold voltage. The addition of a potentiometer allows the output voltage to be set arbitrarily, so long as it exceeds the threshold voltage of the MOSFET.

  5. Tomi Engdahl says:

    Illustrating the advantages #SiC MOSFETs offer in power #electronics
    #transistors #PowerDesign

  6. Tomi Engdahl says:

    This #solar day lamp design can provide lighting when #power from PV panels is limited #DesignIdeas #CircuitDesign

  7. Tomi Engdahl says:

    Stop RF “Radio Frequency” Interference! [Ways To Solve Noise Issues]

  8. Tomi Engdahl says:

    Low noise solid state relays suitable for use in professional food equipment and commercial, industrial, and home appliances

  9. Tomi Engdahl says:

    Should you buy a GaN Power Adapter? Or is it a scam? || Testing GaN FETs!

    In this video we will be having a closer look at GaN FETs in order to find out whether they will improve power electronics products in the future. For that I got myself a commercial GaN power adapter which I will compare with a more traditional power adapter concerning their efficiency. Afterwards I will measure the resistance and switching speed of a proper GaN FET and finally use it in a buck converter circuit to demonstrate the difference to a normal MOSFET. Let’s get started!

  10. Tomi Engdahl says:

    Follow The Leader – Voltage Followers & Buffers

  11. Tomi Engdahl says:

    Objective Guide to Op-Amp Rolling – Part 1

    This blog article/post is a deep dive into currently available 8-pin DIP dual op-amps, for those that like to swap op-amps in their designs and/or DIY projects.

    The article will compare the performance of well know op-maps in two configurations;

    Inverted 6dB gain
    Unity gain buffer

    The contenders are:

    Texas Instruments LME49720
    Texas Instruments OPA2134
    Texas Instruments LM4562
    Texas Instruments LM833
    New Japan Radio NJM2742
    Analog Devices LT1352

  12. Tomi Engdahl says:

    .:: EMP BOX ::.
    EMP BOX. Disables Electronics at close range

  13. Tomi Engdahl says:


    All About Pads
    A question that pops up frequently is that of building atteunator pads. Here is what you need to know, in one place.
    What is a Pad? Where can I use them?
    A pad is nothing more than a network made of resistors that creates loss (attenuation) in a transmission line. Pads can be designed with many different attributes: matched impedances, unmatched impedances, etc. You might use a pad to reduce the level of a +4dBu source to -10dBu, or to allow a microphone preamp to handle the signal from a hot microphone in front of a loud source (even with the preamp’s gain trim control at minimum, it still clips).

  14. Tomi Engdahl says:

    RB-AES4X3 Quad 3 Way AES/EBU Splitter XLR Connectors.

  15. Tomi Engdahl says:

    This DIY Variable Isolation Transformer Has Looks to Die For, But Safety First and Foremost!

    Professional test equipment doesn’t need to break the bank or any mirrors! This DIY variable isolation transformer is both safe and sublime!


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