How is sequential firing in electronics achieved?

  • Thread starter Bararontok
  • Start date
  • Tags
    Electronics
In summary: The IC chip performs the function of the electromechanical contactor by driving electromechanical relays.
  • #1
Bararontok
298
0
How are light bulbs turned on and off in sequence for some signs and flat screen televisions?

How are electromagnets turned on and off in sequence to accelerate maglev trains and coil gun bullets?

How are the CCD arrays in electronic cameras turned on and off in sequence to transmit the captured images to the recording device through a serially transmitted electrical signal?
 
Engineering news on Phys.org
  • #2
For simple systems, a timer/clock pulse is generated (eg by an NE555 chip) then fed into a counter chip which will count up in binary (so for each pulse the counter will increment in binary - 0000, 0001, 0010, 0011, 0100 etc). Those binary states can then be combined via digital gates (AND/OR/NOT) to give output signals/states at specific time.

Fancier systems like washing machines use microcontrollers

In the olden days, it was reels with revolving contacts/bumps pressing microswitches.
 
  • #3
Yes, usually the counter will be implemented as a jump counter so that the electrical output can automatically be switched from one output terminal on the IC chip to another output terminal but how is this accomplished electronically within the circuitry of the IC chip? What type of electrical phenomenon makes this possible?
 
  • #4
There is a class of chip between microprocessor and just a bunch of gates called a multiplexer. A good example is the 8 line to 1 line 74151 IC.
These can operate at video frequencies and above.

These are electronic versions of the revolving contacts called actuators or contactors, which were actually pretty sophisticated and reliable so don't sneeze at them either. However mechanical systems are frequency limited to a few kHz at best.
 
  • #5
Yes, how does the IC chip perform the function of the electromechanical contactor but in a solid state manner?
 
  • #6
Depends on the application. In some cases the IC would drive electromechanical relays in other cases a transistor can be used to stick with a strictly solid state design.
 
  • #7
Have you googled the spec sheet or multiplexer in general?

The following is a mid 70s circuit to put 8 channels on a single channel scope.
 

Attachments

  • mpx1.jpg
    mpx1.jpg
    41.8 KB · Views: 429
Last edited:
  • #8
You're looking for power switches. Look up SCR, TRIAC, ignitron, MOSFET, BJT, IGBT. There are others.
 
  • #9
you should also look up how a simple clock or "multivibrator" works. you can actually build a simple one with an op-amp (wired up as a Schmidt trigger), a couple of resistors and a capacitor. the timing of the period has something to do with the RC time constant.

once you have a clock, the rest is all logic, then you need to learn how a flip-flop works. and then a "state machine". this is what you learn in your first digital logic course. you need to learn about AND, OR, and NOT gates, about truth tables, about Boolean algebra, and then about sequential state machines in general. that is when you'll first run into the concept of "microcode".
 
  • #10
You're looking for power switches. Look up SCR, TRIAC, ignitron, MOSFET, BJT, IGBT. There are others.

Not really these are just signal level power requirements.
 
  • #11
Studiot said:
Not really these are just signal level power requirements.

Maybe you missed this one:
Bararontok said:
Yes, how does the IC chip perform the function of the electromechanical contactor but in a solid state manner?
 

FAQ: How is sequential firing in electronics achieved?

1. How does sequential firing in electronics work?

Sequential firing in electronics is achieved through the use of a microcontroller or microprocessor. These small electronic devices are programmed to send electrical signals to various components in a specific sequence, allowing for precise control over the timing and order of events.

2. What is the purpose of sequential firing in electronics?

The purpose of sequential firing is to control the operation of electronic devices in a specific and predictable manner. This is especially useful in complex systems where multiple components need to work together in a specific sequence.

3. Can sequential firing be achieved without a microcontroller or microprocessor?

In some cases, sequential firing can be achieved through the use of simple logic circuits or timing circuits. However, these methods may not provide the same level of precision and control as using a microcontroller or microprocessor.

4. What are the advantages of using sequential firing in electronics?

There are several advantages to using sequential firing in electronics, including improved efficiency, accuracy, and reliability. Sequential firing also allows for more complex operations to be performed, making it a valuable tool in many industries.

5. Are there any limitations to sequential firing in electronics?

One limitation of sequential firing is that it relies on precise timing and can be affected by external factors such as temperature and voltage fluctuations. Additionally, using a microcontroller or microprocessor for sequential firing may add complexity and cost to a system.

Similar threads

Replies
30
Views
3K
Replies
19
Views
11K
Replies
152
Views
7K
Replies
1
Views
2K
Replies
2
Views
2K
Replies
7
Views
2K
Back
Top