Questions tagged [trigger]
A type of oscilloscope sweep in which a *trigger*, or waveform characteristics matching a user-specified condition, will initiate the sweep. A trigger can also be an event, such as a pulse, which causes a circuit to begin performing some action.
178
questions
2
votes
1
answer
73
views
Generating a TTL signal triggered by the falling edge of another TTL signal
I have a power supply that can produce pulses up to a switching frequency of 100 kHz. The power supply has an external TTL signal interface that produces TTL signal corresponding to the level of ...
- 49
0
votes
1
answer
30
views
555 Bi-Stable mode gets triggered by reset pin
I prepared a Bi-stable 555 circuit based on below schematic. Threshold pin is connected to ground as suggested. Many tutorials left it to float. I remember like once I faced some issue by leaving ...
1
vote
0
answers
31
views
Tektronix 2000B series oscilloscope trigger not triggering camera
We have a Shimadzu high speed camera connected to a Tektronix oscilloscope. We got a new cord for the force sensor and since that point the camera has not been triggered correctly.
It used to be that ...
- 11
1
vote
2
answers
92
views
Driving 32 SiC MOSFET gate drivers with one function generator trigger signal
I have been having a hard time finding out how to drive 32 gate drivers for SiC MOSFETs from a single function generator signal of 5 V.
My function generator is a Keysight 33500B. I'm using Genesic ...
- 21
0
votes
1
answer
51
views
Function Between Oscilloscope Trigger and Sampling Storage
I have a query where maybe is stupid but anyway I will dare to ask. How the oscilloscope knows when to start to save the sampling data in his RAM memory in order to process them and display them? I ...
- 373
0
votes
2
answers
104
views
How to properly trigger and measure a modulated square wave signal with an oscilloscope
I'm having trouble getting a stable trigger on my Rigol DS-1202 oscilloscope for a complex waveform. The waveform is composed of a 25.5kHz carrier square wave modulated by a 200Hz square wave, both ...
0
votes
0
answers
19
views
Wide input range Dual Edge Trigger Input (P-Channel N-Channel Linked Pair)
i'm working on a design where I would like to tolerate both source and sink currents as valid inputs, along a wide input voltage range.
Specifically, I would like to have an output logic high for both ...
0
votes
1
answer
75
views
Shift Register 4021 Scheme
out of pure interest and a month of free time, I decided to re-create the schematics of some things I had. One of them was the NES controller. I found the schematic on the Internet and decided to make ...
0
votes
2
answers
43
views
A sensor's idle voltage is 1.1 V, and its triggered output voltage is 5 V. How can I condition the signal to be <0.2 V idle and ~2.5 V triggered?
I'm triggering a high speed camera with an analog chronometer tower that when un-triggered puts out 1.1 V. When an object passes through the tower, it briefly spikes to 5 V. I'm using an old camera ...
- 87
0
votes
1
answer
194
views
555 Monostable Mode Press and Hold Trigger
So, I have a 555 Timer in Monostable Mode, like below. I used a 47uF cap and a 47K resistor for the C and R. I press the trigger switch button and let go, and the output goes high for roughly 2.5 ...
- 87
0
votes
1
answer
48
views
What guarantees are there on when GPIO states are read and written?
I'm fairly new to electronics, coming from software engineering, and it's not clear to me when GPIO states are set or read in microcontrollers relative to a clock pulse.
If on cycle n, I toggle a GPIO,...
- 167
1
vote
0
answers
40
views
Generating trigger spikes around a reference
I'm experimenting with a circuit to use a IR2151 (self-oscillating half-bridge driver) as an el-cheapo MOSFET driver. Basically take away the "self-oscillating" part and trigger the high and ...
- 11
0
votes
2
answers
80
views
Three wire remote controller - wiring to two GPIO pins
My remote camera trigger has three wires (red, yellow, white). The white is shared, and the trigger can complete two different circuits by shorting it with either the red or the yellow cable. One of ...
0
votes
0
answers
108
views
Explain schematic for one-shot trigger
Can you please help to explain following schematic:
How does this circuit work?
What is the purpose of the diode and the capacitor?
- 107
2
votes
5
answers
232
views
How to sense the presence of AC voltage that could vary from 17 V to 230 V?
I have a requirement to sense the presence of AC voltage, that could vary from 17 V to 230 V, and trigger a TLPxxx series optocoupler.
The wide voltage range poses a problem in the choice of a ...
1
vote
1
answer
72
views
Match function generator output phase to line phase
I am new here so my apologies if I am missing pertinent details. I am trying to cancel a 60Hz EM field by sending a small 60Hz AC current through a loop of wire that I am generating with a function ...
- 11
0
votes
1
answer
78
views
DS1102E oscilloscope not triggering above 200mV
Once adjusting the vertical scale of my Rigol DS1102E oscilloscope from 200mV to 500mV the signal appears to be lost. Instead of showing the "T'D" (triggered) icon in the top left it then ...
- 101
2
votes
4
answers
505
views
Convert a 0 V / 3.3 V trigger signal into a 0 V / 5V trigger signal (TTL)
I have a device sending a square trigger signal 0V / 3.3V, with a BNC connector.
(We usually call it a TTL signal, I don't know if it's the common name? is it relative to Transistor-Transitor-Logic?)
...
- 1,966
1
vote
0
answers
190
views
12VDC LED blinks when powered by a PD charger using a USB-C decoy module
I am trying to build a low-voltage LED lamp powered by a USB-C PD power adapter instead of a traditional DC power supply with a barrel connector. Several reasons for this:
USB-C cable is detachable ...
0
votes
1
answer
79
views
Identify types of circuit(s) that would function as stated
I am trying to build a circuit that will have a trigger input, a clock input and an output that is (10) pulses at clock frequency for each trigger pulse.
Would it be multiple circuits (chips) or just ...
- 1
0
votes
0
answers
81
views
I would like to build a delay circuit
I would like to build a latching relay control circuit, controlled by MCU.
I'd like to implement the following:
The idea is from here: https://pdfserv.maximintegrated.com/en/an/AN3288.pdf
The relay I ...
2
votes
1
answer
171
views
Capacitor discharging in a low power active-high pulse circuit
Team, Thanks as ever for your wonderful support. Long time listener, first time caller.
I trying to make a low power active-high pulse (4-8sec RTC interrupt) when a switch is pulled to ground for up ...
- 33
0
votes
0
answers
69
views
Signals below trigger level are still captured by the oscilloscope
I use NI's oscilloscope PXIE-5162 to measure the Na-22 spectrum with Canberra's NaI(TI) photomultiplier tube. I notice that although the trigger level is always kept constant at 0.1V, there are still ...
- 35
-1
votes
1
answer
140
views
Latching interval timer with positive trigger
Can I create a latching interval timer circuit with a 555 chip using a positive trigger (which is not pulsed but remains high during the timing interval and afterwards) without retriggering the timer? ...
- 1
0
votes
1
answer
611
views
How do I get a stable trigger on a digital Hantek oscilloscope?
I'm not a super-expert of oscilloscopes but I used several Tektronix (both analog and digital.)
I have a Hantek DSO4254C and I'm not able to get it to trigger on a sine wave coming from my board. The ...
- 1,253
3
votes
1
answer
475
views
TRIAC self triggering. How can I improve my circuit?
I have designed a circuit board for my Arduino controlled dishwasher, using the following circuit taken from the MOC3043 datasheet. I have used a BTA 16-600BW snubberless TRIAC with a 100 ohms and 10 ...
- 31
0
votes
1
answer
101
views
Monostable (eg CD4538 channel) connecting rise and fall inputs together to generate pulse from rise or fall
I would like to use one channel of a dual monostable (CD4538) to generate a pulse from either a rise or fall single trigger input feed.
If I connect rise and fall trigger inputs together
(or use a ...
- 1
0
votes
4
answers
997
views
Confusion about edge/level triggering interrupt
I have read this answer.
My understanding is, there are actually 2 lines logically:
clock/gating line
event/interrupt line
And the clock/gating line can make the circuit take event input at an ...
- 1,192
0
votes
1
answer
321
views
Read parallel data that is valid in falling edge clock NUCLEO-H743ZI2
I have an external ADC with 2 parallel output pins. Each is 1 bit (2 bits total), with clk_out pin.
I am trying to read the parallel pins using a NUCLEO-H743ZI2 (480 Mhz). I followed the AN4666 ...
- 3
0
votes
2
answers
197
views
Are false positives from (advanced) IR proximity sensors normal? - VCNL36826S
I am working on project where I am using an IR proximity sensor from Vishay - VCNL36826S.
This sensor is observed to give false positives randomly. As I am still trying to catch this rare event, the ...
- 11
1
vote
2
answers
463
views
Why TRIAC is not triggering?
I'm trying to trigger a TRIAC BTA16-800 using an MCO3021 optocoupler. I have a two-channel power supply, in one of them I'm pulsing the optocoupler at 120 Hz and the other channel is configured as a ...
- 13
0
votes
1
answer
40
views
To trigger ON & OFF of an emergency light with external signal
I need to trigger ON an emergency lamp with a (1st signal) signal, and the lamp will be lighted up until the next (2nd signal) signal is received then the emergency lamp will go OFF. How could I do ...
0
votes
2
answers
221
views
Adding a buzzer to an existing LED
I have a set top box. It has a 3 mm green LED (on the front panel) that lights up when I connect the dish coax cable (signal LED).
I measured the voltage across the LED. It has 0 V when the dish cable ...
- 11
0
votes
0
answers
465
views
CD4069 toggle switch
How to connect the trigger out instead of the switch? Like a toggle switch. The first trigger out activates the relay and remains ON infinity, the second trigger out deactivates the relay and remains ...
0
votes
1
answer
471
views
Confusion with trigger controlled analogue output of a DAQ board
I came across this article, and regarding the DAQ trigger and analogue output part I'm confused.
If I don't get it wrong the DAQ generates particular analogue voltage levels for X and Y of the galvo-...
- 12.2k
1
vote
3
answers
204
views
How to trigger an 8 channel relay module with an air coil and moving magnet
I just bought this 8 channel relay module on Aliexpress, and I'd like to try to trigger it using an air coil and a moving magnet, but I'm unsure how to connect the coil to the trigger and collect the ...
- 119
1
vote
2
answers
88
views
At what value should I choose the MOSFET resistors for the MOSFET triggered by the MCU?
I have added a picture of my circuit.
Vcc = 5 V and Rled = appr. 600 Ω.
So, I_Rled_current = 6-7 mA.
The MCU is an ATmega328p.
MCU pd1 and pd2 are logical high and logical low.
What should the values ...
- 35
0
votes
0
answers
104
views
How to stabilize this CV triggered toggle (555 timer latching switch) when fed with two gates?
I created the prototype for a modular synthesizer module. The project goal is an AND gate that is fed with two control voltage inputs (A and B with an Vpp around 5V). There will be two outputs: the ...
0
votes
1
answer
53
views
Advancing the clock of a CMOS IC with multiple signals
What would be the best way to advance the clock of a CMOS OC from multiple signals?
In my situation the "upper" signal puts the system in working and the system itself generate the next ...
- 335
0
votes
1
answer
68
views
Level shifting a non-periodic signal
I have an RFID reader that sends a high 5V logic level when it is triggered (RFID tag is seen by the antenna).
I want to then use this 5V output to trigger an ESP32 to turn on an LED and also send an ...
- 2,513
1
vote
2
answers
516
views
Controlling a FESTO solenoid valve with Raspberry Pi - Trigger Issues
I'm currently working on a project for university, where I want to control a Festo solenoid valve (MHJ10, https://www.festo.com/cat/en-us_us/data/doc_enus/PDF/US/MHJ_ENUS.PDF) via a Raspberry Pi GPIO. ...
- 23
0
votes
1
answer
338
views
Sending / Receiving trigger signal wirelessly or through Ethernet
Simple engineer with no background in electronics/electrical engineering here.
I have 2 instruments (emitter and detector) that are synchronized by a Trigger signal. This signal is sent via BNC cable.
...
0
votes
0
answers
89
views
One-Shot circuit has problems with slow voltage ramps
I'm using this circuit:
simulate this circuit – Schematic created using CircuitLab
The circuit is powered by "24V" , "24V ENABLE" is the trigger. The circuit should act like ...
- 457
2
votes
3
answers
406
views
555 timer won't trigger monostable mode unless I add a switch between R12 and ground?
I have this setup which is a part of a bigger circuit to control motors.
This is supposed to be a timer in monostable mode with about a minute of hi output when triggered.
The lines going down are to ...
- 21
0
votes
1
answer
188
views
How can i turn a DPST button in to a DPDT?
How can i turn a DPST button in to a DPDT?
I've replaced all the stock rocker switches in UTV, got all 14 of them done except for one all to Push Buttons. The push buttons are SPDT, "on/on" ...
1
vote
2
answers
88
views
Moving AI IP into new FPGA. Is the trigger for reading ROM an address change?
I'm confused about the trigger for reading ROM.
I want to read one of 4 k bytes but it appears the clock is free running and may be continuing to read the same address while I'm processing the byte I ...
- 13
0
votes
2
answers
1k
views
Analog Oscilloscope Flickering Signal Problem
I am using BK Precision 2125C Dual Trace Oscilloscope (30 MHz), which is analog. I'm trying to observe signal generated by the output of microprocessor. I'm seeing flickering signal (quickly moves ...
- 2,452
0
votes
1
answer
167
views
What kind of electronic component is this?
I am trying to repair the flash of a P900 camera, since it gives a burning smell after being used.
After disassembling the flash unit, I came across this part for which I need some professional eyes ...
- 121
0
votes
2
answers
476
views
Oscilloscope: trigger and multiple periods of the signal
I am trying to understands the basics of an analog oscilloscope trigger. As stated here,
Instead of collecting a single snapshot of the input signal, an
oscilloscope repeatedly updates the display ...
- 748
2
votes
0
answers
133
views
Low latency wireless trigger
I am working on a project consisting of a sensor and receiver connected via Bluetooth 5.2. When the sensor receives a start signal from the receiver, it will begin sampling readings at ~10kHz and ...
- 79