Questions tagged [high-frequency]

This tag marks questions related high frequency (radio) circuits.

Filter by
Sorted by
Tagged with
0 votes
1 answer
54 views

Why is the frequency response from my 1X and 10X probe seem to be converging with increasing frequency?

I'm a Mechanical Engineer trying to get into electronics so please excuse my lack of understanding. I'm feeding a 5.0 Vpp sine wave into my SDS 1202X-E scope from my signal generator (see image below)....
user351001's user avatar
1 vote
0 answers
21 views

High frequency output between two phases [closed]

I have 3 phase ac generator , of late its frequency between two phases comes 100 hz although it is rated for 50 hz. Any idea whats wrong in this. AvR seems to be fine as changing AvR doesn't give ...
APK's user avatar
  • 11
0 votes
2 answers
44 views

What is the key circuitry in a form of high frequency signal generator that means power would be sent and reflected when there's an open load

Ive asked enough questions to explain why when there is an impedance mismatch there is power reflected which from my understanding is because there is a reflection of the waves, and also the cause of ...
George kirby's user avatar
0 votes
0 answers
20 views

On-chip Co-planar Waveguide Design on Si – SiO2 Substrate

I want to design, simulate, and fabricate on-chip Coplanar waveguides (no bottom ground) on a Silicon Dioxide layer 5um thick on a Silicon 500um thick wafer. The metal electrodes will be 1um thick ...
Ravi Pradip's user avatar
0 votes
2 answers
15 views

Debugging PLL STW81200TR not locking

I need a bit of debugging help with SWT81200 PLL that I am using on my custom designed PCB. I am able to configure registers through SPI communication, but the problem is that I am not able to achieve ...
Vasja Pira's user avatar
2 votes
1 answer
157 views

What is the purpose of this long capacitor/inductor chain on a DDS IC evaluation board?

Image of the B output stage of the EVAL-CN0304 AD9834 DDS Evaluation Board IOUT_B is a current source, not potential source, so the initial say half of the circuit I get. The resistor gives us a ...
thomasaronford's user avatar
1 vote
0 answers
36 views

How to provide a low response time <1µs constant current source up to 1.5A

I need to provide a constant current source that can provide up to 1.5A current and a compliant voltage of 0-40V, with a low response time of <1µs. How should I approach this problem? Common bench ...
hailstone's user avatar
0 votes
4 answers
104 views

Measuring a 10-30 ns pulse width

For my school project over summer holidays I was tasked to measure a 10-30 ns impulse of a laser. So far I got the impulse on the oscilloscope, which I will run through a Schmitt-Trigger to get a ...
Syco's user avatar
  • 1
0 votes
2 answers
93 views

Why can’t I find fast transistors and same fast diodes?

I am trying to make a 30 GHz 32 (or 64 bit) counter on flip flops. Ready counters do not satisfy me due to max frequency and price, so I decided to make it on my own from flip-flops. Ready flip-flops ...
Stdugnd4ikbd's user avatar
0 votes
0 answers
39 views

High swing (Low-voltage) cascode current mirror pole

I have been trying to figure out extracting the exact derivation for the poles, I am only struggling with figuring how the author got pole 8. I am using the small signal for the high swing cascode ...
serdude's user avatar
0 votes
2 answers
75 views

Part guidance: Switching 120 VAC @ 3 kHz in < 5 ms

I want to control electroluminescent wire, which runs at 100 Volts AC @ 1000 to 3000 Hz, with a desired switching delay of under 5 ms. I have used Sparkfuns products in the past, but they are no ...
Thomas Hirsch's user avatar
0 votes
0 answers
55 views

Which of the modern transistors could be a substitute for 2N709?

I need to replace the damaged Q1 transistor, but I don't have a 2N709. I was thinking about 2N2222 because of the similar case type. However, this transistor differs in frequency. In this follower ...
Jerzy Przezdziecki's user avatar
1 vote
0 answers
29 views

How to simulate a Large Structure at low frequency in CST Microwave Studio?

In CST Microwave Studio, I attempted to simulate a large (215x30cm) loop structure at 1kHz. However, CST gives a warning of 'too large' mesh size. The mesh size increases up to 6 Billion, however, if ...
Pessentrau Optiarou's user avatar
0 votes
1 answer
77 views

High frequency voltage to current

I have a signal oscillating at tens or hundreds of MHz (up to 200 MHz expected), with 2.5 V mean and approx 200 mV peak to peak. I'd like to produce a current proportional to this signal at approx 40-...
user12910's user avatar
  • 113
1 vote
1 answer
59 views

Trigger (Flip-flop) with under 3 ns delay?

I want to make nanosecond clock timer as a 64-bit counter. There is a scheme (4-bit): I am trying to find JK-trigger, or other, that can work with 300 Mhz clock speed, at least, i.e. 3.3 ns at most, ...
Stdugnd4ikbd's user avatar
0 votes
0 answers
46 views

Calibrating the R&S FPL 1003 Spectrum Analyzer

I am setting up an EMC test bench and I have a spectrum analyzer(SA): The Rohde and Schwarz FPL 1003 Spectrum Analyzer. I am trying to conduct some preliminary tests to ensure that the results seen on ...
ORion's user avatar
  • 57
2 votes
2 answers
85 views

Shielded -vs- Non-Shielded, running CAN Data Cable w/ 115/200VAC 3-Phase @ 400Hz

*Edited, AGAIN, in an attempt to remove any confusion Settle this debate! I am designing a Harness for testing the functionality of a PDU (Power Drive Unit), operated using CAN (ARINC-825). Prior to ...
joel cox's user avatar
3 votes
1 answer
171 views

Ways to get around amplification limited by op amp GBW?

I'm working on a project that requires me to amplify 70 pA to read out at 10 V (the digitizer I'm using to collect data has a range of 0 to 10 V readout). On top of this, I need to sample my voltage ...
Winston Wilhere's user avatar
0 votes
0 answers
180 views

High speed (100 MHz) full wave rectifier

I would like to build a full wave rectifier of a RF signal (Vpp should be less than 1V) with a frequency of 10 MHz and carrier at 100 MHz. For example, this could be the signal: If possible, the ...
mabeco's user avatar
  • 43
-1 votes
1 answer
165 views

Could a DIY 1 kW portable version of the military non-lethal microwave beam active denial system (ADS) be made?

How would one create a portable 1 kW microwave emitter that projects out a 95 GHz beam to about 5 - 10 feet? What kind of components would be required? I recently came across this fascinating video ...
emtinkerer's user avatar
0 votes
1 answer
61 views

How can I find values for resistors and capacitors for an active bandpass filter with Rauch structure?

I have to find the values of the resistors and capacitors for this type of bandpass filter in order to obtain 105.5 MHz and 99,9MHz. I have found the transfer function, m, wc and the gain: I am ...
Tassanix's user avatar
3 votes
1 answer
292 views

Problem about Instrument amplifier from LM358 at high frequency

I am researching about instrument amplifier circuit by use op-amp is LM358. In this circuit gain is 1 by Rgain=R2=20k, R1=R3=10k. Testing is define frequency range 1 Hz-10 kHz but when this circuit ...
EricSphere's user avatar
0 votes
0 answers
27 views

JFET Hartley Oscillator's Transformer [duplicate]

I have designed a JFET hartley oscillator but I couldnt order the transformer in our circuit. Can anyone help me on this subject. The transformer's operating frequency is 1Mhz to 3.5 MHz and I could ...
Nurullah Çetin's user avatar
3 votes
1 answer
144 views

Why is drain-source parasitic capacitance(Cds) omitted in JFET datasheets?

I've checked several datasheets on JFETs and I cannot find drain-source parasitic capacitance. They either include only Cgs and Cdg or they only include Ciss or Crss. Here are a few high frequency ...
Phill Donn's user avatar
1 vote
1 answer
83 views

Multisim simulation of a current division

I'm currently trying to simulate a current division for three transmission lines that are in parallell (but all of different lengths). I want to study how the current divide itself as we progressively ...
Tanamas's user avatar
  • 313
1 vote
2 answers
115 views

Why is the falling edge slower than the rising edge?

I have a radiation sensor connected to an amplifier and then to an oscilloscope. This is the circuit: The radiation sensor (an LGAD) is connected straight into the "In" terminal, few ...
user171780's user avatar
0 votes
2 answers
112 views

Fast unidirectional level switch from 5 V to 3.3 V

I came up with this circuit. Is it good or bad to use diodes? In my opinion, this is better than a divider or a FET, at least faster, as you can see from the waveforms. Will such a circuit create ...
GriDev's user avatar
  • 3
2 votes
4 answers
146 views

Can slower switching edges worsen the EMI behavior?

A common method (as stated in many electronic design articles/books) to reduce EMI (radiated emissions) of any fast switching circuit is to slow down it's switching edges (reduce tr/tf). This ...
CatastrophicFailure's user avatar
0 votes
1 answer
50 views

In what direction does skin effect take place?

I'm working with some problems with coaxial cylinders and the currents driven in those when considering high frequencies. In such cases, the skin depth has to be taken into consideration. One thing I ...
Tanamas's user avatar
  • 313
0 votes
0 answers
25 views

How to get freq stability with constant offset for PLL synthesizer?

I used ADF5356 PLL synthesizer. And i use reference oscillator freq is 10MHz with initially offset 0.1ppm and stability is 10 ppb. I need to output freq is 3750 MHz. Expected output result: 10MHz × 0....
Purushothaman Jayaraman's user avatar
5 votes
3 answers
673 views

Will this high-frequency PWM LED driver and MOSFET circuit work OK?

I am taking a PWM input (0-12 V) from a TLC59711 (driven by SPI from a Raspberry Pi) and I want to drive a P-channel MOSFET. It is driving a 12 V, 40 W LED. I want to switch at high frequencies, as I ...
Seb Wilson's user avatar
0 votes
1 answer
66 views

High frequency sinks to MOSFET's drain?

I have the following setup on a custom PCB. The WT32-ETH01 module can be normally booted into download/flash mode by holding the IO0 to the GND during the start. The IO0 is also used as a clock ...
Marek's user avatar
  • 143
1 vote
2 answers
172 views

Measure ≥ 200ns pulses (width and interval) as precisely as possible

I have a 0..5 V digital signal with a minimum pulse width of 200 ns. I would like to measure the pulse width and the time between the rising edges of pulses. In my case it would be enough to measure ...
Artjom Eske's user avatar
5 votes
3 answers
1k views

MOSFET is getting very hot at high frequency PWM

I want to drive a Litz wire coil at 250 kHz. I chose Arduino initially and then replaced it with NE555, but the Arduino or NE555 is generating 250 kHz, which is fed in a Litz coil to turn on some LED ...
15 Volts's user avatar
  • 466
0 votes
4 answers
340 views

Matrix is singular

I have checked the other questions concerning this topic, but I can not seem to understand it. Here is my circuit. For some reason, it always says Matrix is singular. Does anyone know how to fix it?
ThorbenL's user avatar
3 votes
1 answer
116 views

What happens to reflections when the distance between a capacitors plates is electrically long?

I understand what happens when a transmission line is terminated with a capacitor but what about when the distance between the plates becomes electrically long? For PCB mounted capacitors I know this ...
Edwin Shepherd's user avatar
0 votes
2 answers
150 views

Creating a 10MHz clock grid

I have a round surface of 1.5 meters in diameter that contains many electronics. What I would like to do is distribute a 10MHz 3.3V clock signal from Teensy 4.0 across the table for 200 ADCs to access ...
Gabriel's user avatar
  • 55
1 vote
2 answers
76 views

Op-amp compensation terminated to negative supply voltage instead of ground

I'm working on an amplifier for a SiPM and we are using the AD8099 amplifier in a transimpedance amplifier configuration. I noticed that in the example circuits shown in the datasheet the compensation ...
user545424's user avatar
2 votes
2 answers
120 views

Air core inductor impedance vs frequency graphs

I wanted an inductor with at least 100 μH, so I used a PVC pipe and some enamelled wire (AWG 21 if I recall correctly) to create an inductor. The inductor does serve its purpose fine as a load ...
Grigoris's user avatar
0 votes
0 answers
84 views

Oscillator with low frequency drift

I need a ~70MHz oscillator with low frequency drift (less than 1%) over a wide temperature range (10°C to 50°C). I dont have any experience with oscillators, so I have no idea which type of oscillator ...
BenK's user avatar
  • 123
3 votes
1 answer
171 views

Considering USB 3.0 Cable and PCB Layout

I'm trying to connect usb Vision3.0 camera to Board. There are cables and other boards between the camera and the board. I am attaching the picture material. I checked a few things. USB 3.0 has 9 ...
user325751's user avatar
0 votes
2 answers
362 views

How ground plane acts as a low impedance path and shielding action of ground plane

I am new to high speed design .Please don't flame me if this question is very basic :) Below statement is from AD application note. (AD Appnote) "The ground plane not only acts as a low impedance ...
Hari's user avatar
  • 1,595
3 votes
1 answer
164 views

Negative pulse at NPN collector when base switches off and reverse-active mode behaves better at HF

I have a system that detects pulses amplitudes with a peak detector, the signal from which is then digitized with an ADC. Pulses can sometimes overlap, so I've decided to "zero" the peak ...
sx107's user avatar
  • 1,075
4 votes
4 answers
605 views

Placing of capacitor close to IC power pin - logic

I have 2 capacitors. The first one is 100 nF and the other one is 1 μF. When doing the layout, which capacitor should be placed close to the IC power pin and why? I have seen in many places that the ...
user avatar
0 votes
1 answer
72 views

Do ADC do averaging of the voltage between 2 samples?

I'm using a 14bit ADC (on a Spectrum PCI acquisition card) at 500 Mhz, but this question is valid more generally. Do ADC do some averaging of the voltage between 2 samples, or do they usually take the ...
Basj's user avatar
  • 1,866
2 votes
2 answers
91 views

Very high ripple at the output of my converter

I need help on how to reduce this ripple at the output of my converter. I already have a 1uF x8 capacitor at the output, butI am still getting loads of noise. Can you help with the best method to have ...
ikenna's user avatar
  • 43
8 votes
3 answers
1k views

How can I create a mist maker with a 9 V DC power supply?

Context Note: I am a beginner with electronics so please provide detailed explanations and add descriptions that are more beginner friendly. I really do want to learn how this all works. I am trying ...
Alex Thomas's user avatar
1 vote
2 answers
206 views

Why are analog signals preferred for high-frequency applications? [closed]

I really don't see what benefit analog signals would give over digital ones in this case.
Ambica Govind's user avatar
2 votes
3 answers
508 views

Why doesn't the whole signal get absorbed by the termination resistor in high-speed designs?

We normally parallelly terminate with a matching (50 Ω) resistor in high-speed designs. Normally, the load/receiver is high impedance, but if we terminate it with a 50 Ω resistor, wouldn't the whole ...
nmr's user avatar
  • 65
1 vote
0 answers
32 views

Microstrip structures identification

I'm currently starting with learning how microstrip structures work. Just for clarification: I'm talking about these here: Microstrips In Power dividers and directional couplers, some basic structures ...
Justin Time's user avatar

1
2 3 4 5
10