Questions tagged [timer]
Circuit to generate a signal at a specific time after a trigger event. The timing can be defined by an RC time constant, or by clock pulses from an oscillator.
1,149 questions
1
vote
2
answers
118
views
Correcting flaws in this 555 module for a timer
I want to simulate a push button with a little circuit. I'm using an IC 555 as a timer. The button is in another circuit (different device), pin A has 2.4 V and pin B is GND, it does activate if I ...
- 409
8
votes
5
answers
867
views
What is the Longest Time I Can Set an Astable 555 Timer?
I am designing a circuit that uses a 555 timer to output a 10% duty cycle pulse train. I don't want to get into the details of what this is used on, as it is not relevant, but long story short I need ...
- 305
1
vote
2
answers
127
views
How to Check For Sustained Input Before Transmitting a Signal
I have a device which has a part of that functions as a power failure alarm. This means, if my SMPS is not delivering power to my circuit then an audible alarm will sound off. This circuit is powered ...
- 305
-1
votes
1
answer
77
views
Why does my CH552T NEC IR sender sometimes produce incorrect codes on an ESP32 receiver?
I’m building a USB IR blaster using a CH552T dev board, a Crowtail IR emitter, and an HS-S23B receiver connected to an ESP32. My goal is to send NEC protocol IR codes at 38 kHz using Timer2 for the ...
1
vote
3
answers
242
views
Pausing a 555 Timer Circuit in Continous Time-Space?
I'm attempting to make a 555 timer circuit with the capability of pausing the timer in a continous time-space.
I'm doing this by disconnecting the timing capacitor from the circuit every time I want ...
- 587
3
votes
1
answer
228
views
Are diodes necessary when powering a pump from two separate motor drivers? [closed]
When wiring a 12V pump to 2 low-side PWM DC motor drivers in parallel, when is it necessary to add any of the four diodes shown in the diagram below?
Sometimes, both drivers will be PWMing. Sometimes ...
- 131
1
vote
2
answers
167
views
Trying to figure out why this LED barely turns on from a 555 timer and a logic gate
I created a circuit and made the schematic in EAGLE.
The idea is I have an LED (and a relay also) that turn on via a NOR Gate (which I built out of 4 NAND Gates). If both the input from my comparator ...
- 168
0
votes
0
answers
87
views
SysTick interrupt setup that wakes CPU from WFI low-power state
I am learning how to set up interrupt and low-power features on STM32F446RE Nucleo board.
So far I managed to configure interrupt of general-purpose timer (TIM3) and successfully wake ARM CPU on the ...
- 101
2
votes
3
answers
151
views
Random increment on button press for a counter using CD4029 and 555 timer
It works well in Proteus (Simulation), but when I implement it, it doesn't work. I'm sure that the hardware connections are correct. Also, the 7-segment doesn't display, for example, the number 2 ...
0
votes
2
answers
103
views
Name of a delay circuit [closed]
I'm hoping someone could help me out here. I need the name of a circuit I can google or a schematic, that when a button is pushed; there is a 3 second delay, then a LED turns on for 5 seconds then ...
1
vote
0
answers
99
views
Double pulse circuit for MOT spot welder [closed]
I have a MOT spot welder and I'd like to add a double pulse option with adjustable pulse durations, and delay. I have two 555 chips on hand that I'd like to use. I know there are other chips and ...
- 77
-3
votes
1
answer
1k
views
How to use C005 timer chip? [closed]
According to the literature has 6 main pins which have power, trigger, output and ground with the other two main pins being for a resistor that sets the time that the output remains high for.
I guess ...
- 13
3
votes
2
answers
201
views
How to create a time delay (24h) using the LTC2956
I’m currently working on a project, for which I’m developing a system that should run for 24 hours. After 24 hours it should turn off to lessen the power consumption. I’m trying to develop this system ...
- 31
0
votes
0
answers
92
views
STM32H7S3L8 measuring HAL_Delay(20) with basic timers TIM6 and TIM7
I am trying to set up timers on STM32H7S3L8.
Here is clock configuration:
I am using TIM6 and TIM7 and as I understand both of them get clock source equal to 300MHz.
I have set their prescalers equal ...
1
vote
3
answers
143
views
Producing quadrature signals using single MCU timer and single OC register per channel
Using a microcontroller timer, is it possible to produce the following signals:
With the following constraints:
use only one timer (can count up or down or up and down)
output compare channel has ...
- 720
0
votes
1
answer
103
views
MSP430 ADC with internal vref not working with USI and UART
I have an MSP430G2231 and I'm trying to get an ADC reading from port 1.5. I'm expecting a range of 2.0 to 3.3V, which I'm dividing to a range of 0.8 - 1.3V with a voltage divider. The divider is ...
- 175
0
votes
0
answers
178
views
Using ADC DMA and TIMER in STM32H723ZG
I'm doing my first project on STM32. My board is STM32H723ZG. I am trying to sample analog signal using ADC. I set its sampling rate with TIMER6 and transfer data directly to DMA. I am actually ...
2
votes
1
answer
172
views
STM32H750: Reset timer on HS USB SOF
I am making a sound card with STM32H750 and USB3300. I am using standard Stm32CubeMX USB driver.
To do that, I need to track the number of I2S sample rate clocks per SOF. The idea is to use TIM5 as a ...
- 1,195
0
votes
2
answers
131
views
Internal system timer oscillations on modern computers - how big can it be?
When I synchronize two computers' system clocks up to 0.5 ms precision using NTP protocol implementation, it reports several tens of milliseconds skew in less than 10 minutes, and up to 3000 ms skew ...
- 101
0
votes
1
answer
102
views
STM8S003 TIM1 prescaler seemingly not affecting anything
I'm trying to use an STM8S003 chip for a pretty basic function, so I'm standing up the TIM1 peripheral to use output compare. Everything seems to be functioning correctly, except that the pre-scaler ...
- 1,592
0
votes
1
answer
109
views
ATMEGA2560-16AU PWM control using AVR-C
I'm working on a microcontroller board that also features a couple of motor drivers which can be controlled using PWM signals. I also intend to precisely control the positioning of the motors using ...
- 49
1
vote
0
answers
27
views
Creating a short signal transmission in HT12E based RF communication
In HT12E we continuously transmit even when the input data pins are not changed.My problem is battery optimisation. I am transmitting only ON/OFF switch state through HT12E based RF module and Since ...
- 11
4
votes
3
answers
883
views
Do capacitor packages make a difference in MLCCs?
I have a circuit which has an RC dependent timer. I got two types of ceramic capacitors, both of them have literally the same value, but different voltage ratings:
1206 4.7 μF, 25 V capacitor
0805 ...
1
vote
1
answer
92
views
Circuit design for a timer and relay
I'm designing a timer circuit that detects white cards with black stripes, which needs to be inserted in a specific position to activate. The black stripe sensor must remain disabled when the card is ...
1
vote
1
answer
114
views
How to implement a blinking led circuit that is dependent on its voltage input?
I am designing a circuit with two LEDs, where one LED will blink when the output voltage (Vout) is 5V and the other LED will blink when Vout is grounded. I am confident in the functionality of the ...
- 13