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40

The diode in this configuration is called a "flyback" diode. A motor consists of a coil of wire which is effectively an inductor (and an electromagnet). As the motor spins, the coil will be turned on and off with the commutator inside the motor which will cause voltage spikes. The diode provides a path for this energy so that it can be dissipated into the +...


18

There is no functional difference in reality. However, your simulation software is stupid and needs to do calculations, so you need to tell it which node you want to represent zero and will become the reference to which every other node is measured (remember that voltage is a potential DIFFERENCE). The circuit with a GND connection has designated that node ...


16

To understand this trick, a beginner needs to imagine what the voltages are (magnitude and polarity), and where the currents flow (direction and path). I know this from my personal experience; that is why, I have visualized these invisible electrical quantities in the pictures below by voltage bars (in red) and current loops (in green). I have considered the ...


8

As a slight aside, I thought I should amplify Tony Stewart's comment. The circuit you're looking at is perfectly fine in principle, but it cannot be used for any but the smallest motors. Put it this way - in order to get much current (and therefor much torque or power) from the motor, you need the voltage to be as close to 5 volts as possible. This means ...


5

Here, as in most electronics, "Ground" simply marks the point in the circuit that we want to call "Zero Volts", and use as a reference when measuring voltages elsewhere in the circuit. It does not usually imply a connection to the earth - we can talk about Ground in portable equipment, or in battery-powered circuits on a plastic breadboard. The Ground ...


4

I remember having similar confusion when first introduced to circuits. There is really not much to it.. The grounds on the left and right need to be connected together. In schematics, they are often split, for convenience and clarity. For the 9V battery, the negative terminal would typically be used as ground. However, you could also connect two batteries ...


3

In answer to your questions, while the circuit will work without the diode, its purpose is to protect the delicate electronic components from very high voltage surges coming from the motor when it shuts off. You see, the windings of the motor act, not only as an electromagnet, but also as an inductor, which stores a great deal of energy in its magnetic field....


2

The GND symbol is not a component as much as it is a label or net name. Ground is just a conductor, an electrical node we designate as zero or the reference potential for our circuit. Those two ground symbols are the same point. You could just replace them with wire that all connects to each other. It's just messy and difficult actually draw wires ...


2

There's plenty of mains AC powered equipment which behave as yours. They have metallic shield to reduce electromagnetic interference. That shield is connected directly or with a big capacitor to the output which the designer considered to be the signal ground or the voltage ground. In addition it's connected to the protective earth wire of mains AC input. ...


1

your ground wire is broken, your tester is showing you capacitive pick-up between the live and the ground. to fix, find the break and repair it. The ground will follow the same path as the live wire so check the first outlet on the bad circuit and whatever is before it


1

On a breadboard, I tend to use the bottom one of the long common rails as the ground or common terminal. This is because ground tends to be the terminal with most components connected to it. If you connect meters, or 'scopes, or signal generators, you usually need one connection to the ground terminal. Using a long trace gives plenty of points at which to ...


1

There is no any difference between these two circuits in this case. But the position of ground has significant role in the circuits. The ground in a electrical circuit is the node where we have our "zero volts". Pre-Information: A battery is something that maintains a certain potential difference across its terminals depending upon its rated capacity. A ...


1

Many simulators compute all voltages relative to some "ground" node, and require that some node have a voltage which is set relative to ground. To accommodate schematics where some groups of nodes are "floating" relative to ground, however, simulators will can often identify islands that don't have any ground connection and, if any art found, select some ...


1

the 1553 bus is mainly used in the space industry, a low signal is equivalent to a negative voltage not zero, if you have a look onto your specification you will see what's is acceptable as the range could be quite wide. Same for a high signal it should be a positive voltage within a specific range. the peak to peak voltage must be >18V


1

This bus is Manchester encoded. This means that one symbol (bit) is encoded as a low transitioning to a high, or a high transitioning to a low. These correspond to 0 and 1 respectively. Therefore, if you want to send: 1 0 0 1 0 1 1 1 the sequence is: HLLHLHHLLHHLHLHL This encoding moves the center frequency up to the bit rate, eliminating the low ...


1

You are on the right track with your comment about the "same potential." PC board traces have non-zero impedance, but have resistance and (more importantly in this case) inductance. This means that when you are running a load with potentially high, switched currents, the instantaneous potential is not the same at all points along the current path. Your ...


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