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Will lower voltage power source supplement/charge higher voltage power source?

Indeed, the current you develop with your solar panel will be "pushed" by a weaker potential than the 12V of your power supply. The resultant is a back flow to your solar panel, or rather no ...
Jean Claude's user avatar
3 votes

Can a voltage higher than LED maximum be used when using constant-current LED driver?

The sink driver requires 0.8V to get guaranteed output current, so for 2.9V maximum Vf LEDs you should have 3.7V supply voltage minimum. It won't hurt the LEDs but you might not get full current or it ...
Spehro Pefhany's user avatar
3 votes
Accepted

Is a capacitor a memoryless system?

then the current only depends on the derivative of voltage at that particular instant of time only, You are just trying to shift the memory to the voltage input, rather than the capacitor state. The ...
Neil_UK's user avatar
  • 169k
4 votes

What makes a MCU capable of higher temps than another?

They're probably the same except the testing limits for the higher temperature version would be tighter since they have to allow for more change in order to guarantee proper operation at the higher ...
Spehro Pefhany's user avatar
3 votes

What makes a MCU capable of higher temps than another?

We probably can't know for sure for any particular device, short of the manufacturer saying so*. But it is common industry practice that a given chip design is tested for different parameters (...
Tim Williams's user avatar
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3 votes

5V on DP and DM pins on FT232RL?

Short answer: No, you should not Longer answer: Sure you can do that. It might destroy your chip but that doesn't technically mean that you can't do it. It's even written right there: So: Don't do it....
kruemi's user avatar
  • 3,539
0 votes

Protective-Earthing the chassis with the earthing point being the star-point - How does it keep the Chassis at Earth potential?

Earthing can't solve all problems. The general mass of the Earth can be assumed to be close to 0V. But if one of the phase wires, say L1, touches the ground near you, it will locally raise the ...
Simon B's user avatar
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8 votes
Accepted

Why does IPC 2221 require so much more spacing at elevation?

It comes from the Paschen's Law. The following graph is a Paschen curve taken from this research. The graph may look a bit awkward to make a conclusion as "required clearance increases with ...
Rohat Kılıç's user avatar
4 votes

Why does IPC 2221 require so much more spacing at elevation?

It's more of a one (or two, in this case) size fits all strategy. If you don't want to deal with calculating the exact factor for the altitude at which you'll be operating, then the values given will ...
vir's user avatar
  • 20.3k
0 votes

Can I get the internal resistance of a capacitor from the voltage, capacity, and construction type?

EDIT: most of this answer is wrong when dielectric barrier is small. But I'm leaving it here for history's sake. Skip to the edit below for a better answer Everything I know about capacitors leads me ...
Joseph Summerhays's user avatar
2 votes

Why does a smaller capacitance equate to a larger voltage drop physically?

Let's make an analogy to two glasses of milk. They both have the same height, H. The base of glass A has an area of its base of A1. The area of glass B is B1=2A1. So to fill glass B to height H ...
RussellH's user avatar
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0 votes

Why does a smaller capacitance equate to a larger voltage drop physically?

I was in the same loop of question. But I realized that voltage source is not equal to voltage drop. Voltage drop is the difference between 2 points of voltage. If I have 10 and it became 7 then the ...
Allein Don Tan's user avatar
3 votes
Accepted

Why do I have to increase the current by 2V when I am using a transistor?

It is dim because the collector-emitter saturation voltage for your transistor is ~2V. Use a logic level MOSFET and a current limiting resistor. You won't be able to get full brightness with a 3V ...
vir's user avatar
  • 20.3k
1 vote

Connecting Two 24VDC Power Supplies

Having multiple supplies is possible, as long as you ensure common ground and avoid any cross-feed between the Supplies. Different question: Why not use a stronger supply to feed the whole circuit in ...
S_G's user avatar
  • 624
0 votes

Connecting Two 24VDC Power Supplies

It is better for you to connect both GND and make one reference GND. So you can avoid any noise in data logging part.
Nima Azad's user avatar
0 votes
Accepted

Voltage stabilization

Sounds like you have at least one of two possible issues or both. The first possibility is that your 5-volt DC power supply is undersized or cannot supply the current demand. The output of the 5-volt ...
Dereck's user avatar
  • 652
1 vote
Accepted

Multiple voltage source problem from Boylestead

The values for Va & Vb you stated are correct for the diagram you drew. If the book does not agree then either the book is incorrect, or you have misstated the question. Perhaps V2 is not a ...
Fabio Barone's user avatar
  • 5,317
0 votes

How do I change the output voltage of the LM7805?

It is very interesting to hear about regulator 7805 .in my experience If i neede a few volt more at the output of regular 7805.l added a zenor diode between Ground pin of regulator and Ground ...
Mesh Tech's user avatar
1 vote

Positive to negative dial?

Basic idea There is something contradictory about this simple device called a "potentiometer" (not only that it is called a "meter" but it doesn't actually measure anything) ...
Circuit fantasist's user avatar
1 vote

Positive to negative dial?

I just wanted to expand on the circuit above that is using the ground trick. If you only have one voltage source, you can use a voltage divider instead to make it work. Basically resistors will split ...
Noah Graber's user avatar
2 votes

Why is the power conserved in a phone charger?

I don't understand because in a generator or a battery, when the voltage increases, the current also increases according of the resistance in the circuit because U=RI. Why does the current increase in ...
Tanner Swett's user avatar
  • 3,449
1 vote

Why is the power conserved in a phone charger?

Why is power conserved? Why does the increase of voltage not increase current? Because we choose components, topologies and, designs that attempt to conserve power as much as we can. It's a vital aim ...
Andy aka's user avatar
  • 465k
0 votes

Why is the power conserved in a phone charger?

why is power conserved? The Nature just works that way. That means: our Universe happens to have this power conservation property. It follows from more basic laws, but that's how it is. Power cannot ...
Kuba hasn't forgotten Monica's user avatar
0 votes

Why is the power conserved in a phone charger?

You are right, U=R*I is always true for a pure resistive circuit (where only DC is involved!) When a transformer (or switching regulator) is present, you have 2 circuits, one on the primary side and ...
Stefan Wyss's user avatar
  • 7,653
0 votes

Should a diode be placed between the output of voltage regulator and the battery?

The diode may be required to prevent reverse current flow from the battery, when the charger is switched off.
vu2nan's user avatar
  • 18.8k
1 vote

Why does a 230V 16A socket supply only the needed current to loads?

If I connect a 150W laptop charger to a socket that supplies at home 16A 230V, it will only draw the necessary amperage needed for the laptop charger at 230V. Why? The definition of electrical power ...
Fabio Barone's user avatar
  • 5,317
0 votes

Why does a 230V 16A socket supply only the needed current to loads?

Your socket rated at 16A does not know how many hundred or thousand amps are available from your electricity provider and it also does not know how much your laptop needs for charging. If you connect ...
Justme's user avatar
  • 158k
0 votes

Which one will turn the ceiling fan faster? Current, voltage, or power?

There is a connection between current and voltage. Thus, you can not feed 1 volt and make it draw 5 amps. This depend on the resistance of the motor. If you feed it 5 volt and it draw 1 amp, then the ...
Klaus Nielsen's user avatar
3 votes

Which one will turn the ceiling fan faster? Current, voltage, or power?

For a given fan, you only have one degree of freedom: if you set a voltage, then there is only a single possible current (and a single possible power). And if you set a current, then there is a single ...
Sandro's user avatar
  • 7,697
0 votes

Circuit that offsets input voltage to exactly 0 V

Logarithmic Amplifier: \$ V_{log} = k \log(V_{in}) \$ Differential Amplifier: \$ V_{out} = V_{log} - V_{ref} \$ Integrator (Automatic Adjustment): \$ V_{ref} \text{ adjusted by feedback to keep } V_{...
zeraoulia rafik's user avatar
0 votes

Circuit that offsets input voltage to exactly 0 V

The problem you have is that in order to offset the output of the function to what it will be when it reaches a reasonably stable state you have to know what the voltage at that point will be. For ...
GodJihyo's user avatar
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