Phil Frost's user avatar
Phil Frost's user avatar
Phil Frost's user avatar
Phil Frost
  • Member for 10 years, 11 months
  • Last seen more than 2 years ago
  • EN82jm
157 votes
4 answers
77k views

How can I efficiently drive an LED?

59 votes
5 answers
21k views

Why would one drive LEDs with a common emitter?

47 votes
1 answer
60k views

How can I implement regenerative braking of a DC motor?

39 votes
7 answers
19k views

Why is an inductor not a good antenna?

37 votes
6 answers
52k views

What is the difference between the magnetic H field and the B field?

30 votes
7 answers
8k views

What makes a "balanced" audio signal?

28 votes
3 answers
2k views

What happens at the end of a transmission line?

26 votes
1 answer
29k views

How can I measure back-EMF to infer the speed of a DC motor?

25 votes
3 answers
11k views

Why should I worry about a motor causing my supply voltage to shoot up when the back-EMF can't exceed the supply voltage?

24 votes
6 answers
112k views

How do ceiling fan controllers work?

20 votes
6 answers
3k views

What's the purpose of crossing over in the middle of a toroid winding?

19 votes
2 answers
2k views

Why does connecting a high-current device to my digital circuit cause weird behavior?

18 votes
4 answers
10k views

What's the importance of source impedance termination?

16 votes
2 answers
11k views

What is MOSFET gate drive capability and why do I care about it?

16 votes
2 answers
958 views

How, if at all, can a memristor be emulated with active components?

16 votes
3 answers
4k views

In a DC motor, is there one commutation point that is optimal in all respects?

15 votes
4 answers
5k views

Can a charge-pump be 100% efficient, given ideal components?

15 votes
2 answers
8k views

Why don't hall effect current sensors exist for low currents?

14 votes
1 answer
2k views

Is it possible to reject noise traveling on the outside of a coaxial transmission line?

13 votes
5 answers
3k views

Is it valid to consider back-EMF in a DC motor equivalent to increased inductance?

12 votes
3 answers
3k views

Why does CircuitLab have the MOSFET symbols it has?

12 votes
4 answers
10k views

Mathematical proof that RMS voltage times RMS current gives mean power

12 votes
5 answers
6k views

Just how does high VSWR damage RF amplifiers?

11 votes
3 answers
9k views

What is the physical significance of the unit ampere/meter in magnetics?

10 votes
4 answers
10k views

How can a capacitor store charge whilst also passing current?

10 votes
5 answers
28k views

meaning of MOSFET "linear region" in the context of switching losses

9 votes
2 answers
3k views

What is the importance of the \$50\Omega\$ resistors in this RF op-amp circuit?

9 votes
1 answer
7k views

What, if anything, makes shielded loop antennas so great at rejecting local noise?

8 votes
3 answers
1k views

Are the currents that travel on the outside of coax really "common mode"?

8 votes
1 answer
1k views

Do long transmission lines degrade rise/fall times, and if so, by what mechanism?