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Twisting wires reduces the magnetic loop area of the wires, this has two implications:
Reduced susceptibility to noise from magnetic fields, with twisted wires an a smaller magnetic loop area, external magnetic fields will induce less current in the loop made by the wires than straight cables.
Reduced magnetic radiation from loads that are switching. A ...
8
6170W1D012G is an LG part number. Primary 120v. HT secondary is 2210v 500 mA. If you have to ask, as has been said, you do not know enough to do this safely.
8
No. Do not use a Microwave Oven Transformer (MOT) for a Tesla coil.
It is the wrong impedance. The output voltage is too low (around 2kV), spark gaps will not fire reliably. The output current is too high (500mA), if it bites you, you will probably die.
The correct transformer to use is an old style (iron core) Neon Sign Transformer (NST). The output ...
5
It would reduced radiated noise. No specific reason to really avoid it since the only real reasons are reduced heat dissipation and overkinking the cable which shouldn't happen if you do it properly.
It would also reduce noise that is coupled to the lines that enters the power supply (by ensuring the noise is picked up "identically" on both lines), but that ...
4
PSUs aren't designed to operate in parallel and "share the load".
This is because each PSU will have their own feedback loop to set the output voltage. The output voltage is set from an internal reference. These references can never be exactly the same so the PSU's output voltages will always have a (small) difference.
The PSU with the highest output ...
3
Another way can be by modifying the -12 V rail:
If you see the schematic of the power supply, you can see that there is no difference between the +12 V rail and the -12 V rail, except the rectifier diodes and the electrolytic capacitor in the output.
If you get the rectifier diodes (from another PC power supply) you can put the high ...
2
Simply use a readily available linear voltage regulator IC. They cost cents and are easy to use, and actually do work reliably across their full range. Current limiting can be achieved either by a linear supply with current limiting built-in, or using something like a low-side shunt resistor (much smaller than 12 Ω) (diode-)attached to the feedback port of ...
2
Should I just place a big ground plane on the bottom and connect
everything? Or perhaps a star topology?
Big ground planes are best in most designs. They reduce inductance and resistance of return currents because there is more copper for the current to flow on. They also increase the amount of capacitance to other traces/planes which is good to knock ...
2
You need to define 'better' before anybody can suggest a better way.
You have 360 Joules to get rid of.
The easy way is to turn it into heat. 360J is not much, in terms of the thermal pulse capacity of a large metal element resistor. Calculate the right size, switch it across your capacitor, it will heat up, job done. This is likely to be the cheapest, ...
2
You have to tie the inputs of unused MOS gates to ground or Vdd (recommended) or they will pickup random noise and amplify it. It the case of Schmitt triggers, this may cause them to flip the whole range with their full speed.
Also, you should add a 100nF ceramic decoupling cap right at the chip to care for that switching noise, which you cannot avoid ...
1
I suggest you use a ceramic capacitor with a small resistor in series equivalent to the ESR of a similar size tantalum capacitor. That's on the output, of course, there's no reason for the resistor on the input capacitor.
That gives you the stability (as guaranteed as you'll ever get) and none of the disadvantages of tantalum caps, at the virtually ...
1
This may help you. I am currently working with the voltage regulator LD11173v3 and I actually run some tests with it. I am using the recommendations of design of this circuit and the output seems to be pretty stable. I am working with high freq signals so mi picture results are not suitable for you now but I tested the performance with inputs from 3 to 10 ...
1
If ESP8266 is powered via a dedicated power supply 220V AC → 3.3V DC, does it worth it to put ESP to deep sleep in order to reduce power consumption?
Adding to whiskeyjack's answer:
Most supplies these days are optimized for very low standby power draw. On a very light load, they will go through a cycle of: stop switching and go to sleep, let the output ...
1
If you are thinking the power supply will keep wasting same power whether you use it or not, then you might be wrong.
These power supplies also have a standby state similar to sleeping state of your MCU. When you are not drawing power from these power supplies, they will waste very little power typically 30 mW to 300 mW depending upon design and quality of ...
1
Generally you cannot do this safely without adding a lot of complexity or ballast resistors that waste power, degrade regulation and don't allow full current sharing.
There are some power supplies which are designed to be paralleled which is a feature (sometimes optional) and will be mentioned prominently. For example, the excellent MeanWell RSP-1500 can ...
1
To answer the general question, to suss out the basic specs of a power transformer drive it backwards. This is how we did it in engineering school with pole transformers.
You apply 120vac to the HV secondary of the transformer, then measure the voltage on the primary. (Note: Be sure to fuse the 120v supply.) This will let you calculate the ratio of ...
1
A series resistor will not achieve what is required - the voltage has to stay above 12V for all currents until you get to the current limit point, and then it must collapse below 4.5V. The supply must be able to supply the input current for all the devices on the line (eg 2mA max for each control gear) without the voltage dipping below 12V, but when low ...
1
Consider exciting the high voltage secondary (at 60 Hz) and measuring primary voltage to get an idea of the turns ratio. It should be pretty simple math past that.
I agree with other comments that you might want more experience and/or meaningful oversight from your professors for this project.
1
Your battery maybe have a problem. If there is a 3.3V voltage regulator in the nodemcu you will have to put at least 3.7 volt there. Maybe your battery is not capable of supplying 3.7 volt.
1
Maybe your power bank or the power management system of the phone itself is not able to supply enough power for charging and power for normal phone operation.
I.e. you may only charge while the phone is in stand-by or operate the phone normally but without charging.
If e.g. charging (+ stand-by) consumes 7W and nomal operation consumes 5W , the power system ...
1
You may want to re-consider your requirements with assumptions in specifications.
Current sharing multiple power supplies can be unstable with a light load on the source that is barely supplying current when there is a load disturbance on 2 shared sources regulating on the same load.
The effective loop gain drops when a regulator is driven by another ...
1
I'd like to take a different approach here...
Why not design an active-power supply system? By active I mean, you can use a microcontroller + PMOS setup.
Note that I don't need the load sharing to be perfect, but I'd like to
avoid serious issues. I originally thought I could just use a
P-Channel MOSFET, but after some research have learned that when ...
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