All Questions
22
questions
0
votes
1
answer
51
views
Current varies with constant firing time in an SCR
Please bear with me as I am not a power electronics guy.
I have a circuit in a battery charger that triggers SCRs, attached here. I am generating the fire pulse from a microcontroller at a constant ...
- 159
2
votes
4
answers
1k
views
What does the RMS value of a DC current waveform represent?
I understand (or at least think I understand) the math and calculation of RMS values and that it generally is used for representing equivalent power of non-DC circuits, like typical sinusoidal AC ...
- 41
0
votes
0
answers
130
views
High-frequency pulsed current source not pulsing full current as expected (Keithley 228A + MOSFET switching)
I'm trying to create a pulsed current source (square wave, 50%, 0-40 MHz, 2 A p-p). For this I'm using a Keithley 228A 0-10 A current source, and a custom board consisting only of a MOSFET plus driver....
- 51
0
votes
0
answers
59
views
How can I boost the output current of this pulse generator (LF353, supplied with ±15 V) to above 25 mA?
I have a pulse generator design. Everything works fine, but it is required that the output current is above 25 mA. (The 9.69 kΩ is just a variable resistance to modify the output frequency.)
...
- 83
2
votes
1
answer
381
views
Why does a MOSFET or IGBT's surge current rating stop increasing with decreasing pulse width beyond a point, unlike thyristors?
Thyristor
The surge current rating of a thyristor increases as the width of the pulse decreases. For a single non-repetitive pulse, it's not uncommon for a thyristor to have a surge rating that is 10x ...
- 7,218
0
votes
3
answers
682
views
High voltage, high current pulse pulse power supply
How do high voltage high current pulse power supplies work? For example in electrical discharge machining (generating sparks that remove metal,) a single square pulse can be as small as 1 microsecond (...
4
votes
3
answers
717
views
Can a pulsating signal in which the direction of the current may not reverse radiate from an antenna?
Normally an antenna uses a sinusoidal wave whose positive half-period corresponds with positive direction of the current and vice versa. A pulsating signal/current is a signal in which the direction ...
- 41
2
votes
3
answers
524
views
Why does the PMOS burn out in a buck boost converter when I increase the power supply voltage?
My MOSFET warms up and even burns out when I change the power supply
to 8V. I get an input current of 1A , and the MOSFET burns.
This is the datasheet.
I dont know why. I have an IRF9540n MOSFET.
...
- 61
2
votes
5
answers
717
views
pulsed current with 200 kHz squarewave signal
I use this circuit to obtain pulses as close as possible to the input signal pulses on the 1.5 Ohms resistor. The MOSFET is FPQ50N06 and the transistor is BC239. The circuit gives good results on 25 ...
- 21
0
votes
1
answer
74
views
Measure or detect high current pulse 600A+/15V without osciloscope
How to measure or detect high current(600-800A) pulse (50-100ms)
without osciloscope?
I don't have any osciloscope now, but i need troubleshoot
one spotwelding machine.
I need to know how much ...
- 1
0
votes
7
answers
18k
views
How can I light up 3 LEDs in sequence but only one at a time?
I have 3 LEDs in a row on a breadboard. I want to simulate a visual depiction of a current pulse by lighting up LED #1, then turning that off and lighting up LED #2, then turning that off and lighting ...
- 155
0
votes
2
answers
226
views
If I have pulsed dc current going though an electromagnet, with the magnetic field mimic the current at higher pulsed dc frequencies?
If I have pulsed dc current going though a copper wire electromagnet with no core , will the magnetic field mimic the current at higher pulsed dc frequencies?(such as ghz)
- 33
0
votes
1
answer
138
views
Spec sheet for a pulse generator: Interpreting current output
I am looking at the specifications of a device that produces a narrow pulse waveform, direct current, pulse duration < 1 ms, frequency variable from 5 to 500 Hz. The specs for this device say that ...
- 161
0
votes
0
answers
404
views
Need help with current pulse input to an analog circuit
I have been struggling to solve an issue about signal conditioning an instrument with an analog circuit. First I would like to explain the instrument very briefly:
There is a windmeter which is ...
- 12.2k
2
votes
1
answer
2k
views
Ultrasound project - voltage/current, pulse width
I need help with my ultrasound project.
My plan is to generate -170 V powering voltage with MAX1847 DC/DC from 5 V. Excite the transducer (2,25 MHz, 50 ohms at resonant freq) with square wave (pulse ...
- 121