Synthesis of a decoder for 7-segment LED display

Thread Starter

NBAHbI4

Joined Nov 29, 2018
12
Greetings.I need your help regarding to Synthesis of a decoder for 7-segment LED display.Here is the task:
Synthesize a 7-segment indicator decoder – a combinational logical schematic with three
inputs and one output corresponding to the canonical disjunctive equation which matches the
task data.Realize the schematic on a breadboard and verify it.

Here is my number:Capture.PNG

There are no dedicated restrictions regarding the assembling, as well as the schematic of
the decoder. This is why all available types of ICs can be used: 4069 – six invertor IC, 4073
(if available) – triple 3-input AND IC, 4082 – double 4-input AND IC, 4075 (if available) –
triple 3-input OR IC and 4072 - double 4-input OR IC, as well as decoders 4555 and 4556.
 

dl324

Joined Mar 30, 2015
16,845
For homework, you need to show your best effort. Then we can see where you're having difficulty and guide you to a solution.

You now have two posts for the same question. If you can't delete one, ask a moderator to do it for you.
 

Thread Starter

NBAHbI4

Joined Nov 29, 2018
12
For homework, you need to show your best effort. Then we can see where you're having difficulty and guide you to a solution.

You now have two posts for the same question. If you can't delete one, ask a moderator to do it for you.

I have problem with making this schematic on breadboard.
 

dl324

Joined Mar 30, 2015
16,845
Why do you have 4 inputs in the truth table? The problem stated that you have 3.

You only show one output, but you need one for each segment.
 

Thread Starter

NBAHbI4

Joined Nov 29, 2018
12
I can use AND Gates,Or Gates,Decoder 4555 or Decoder 4556 and Seven Segment Display.
And now I should somehow made it work to make segments in my number glow like shown in task.
 

Thread Starter

NBAHbI4

Joined Nov 29, 2018
12
This is my laboratory task.
Available are: 4555 decoder,4556 decoder,AND Gate with 2 and 3 Inputs,NO Gate,OR Gate with 2 and 3 inputs.
 

Thread Starter

NBAHbI4

Joined Nov 29, 2018
12
Yes,but how?I have no breadboard at home and I would do my laboratory soon and have no idea how to synthesize this schematic.
 

dl324

Joined Mar 30, 2015
16,845
You've done your truth table outputs the reverse of what most would do, but it'll work. Now solve the Kmaps.

It looks like you intend to use the gate outputs to sink current for the LEDs. That's also unusual because the outputs won't sink much current at 3V. You should also use current limiting resistors because not using them will be considered a mistake to most.
 

Thread Starter

NBAHbI4

Joined Nov 29, 2018
12
You've done your truth table outputs the reverse of what most would do, but it'll work. Now solve the Kmaps.

It looks like you intend to use the gate outputs to sink current for the LEDs. That's also unusual because the outputs won't sink much current at 3V. You should also use current limiting resistors because not using them will be considered a mistake to most.
We have no resistors at all.We are able to settle without resistors.
 

sc0tch

Joined Nov 6, 2018
64
We have no resistors at all.We are able to settle without resistors.
How does a school with an EE program not have resistors? and how does anybody even outside of academia get all these gates and displays and not at least have a basic set of resistors? You will end up burning the diodes out of your 7seg displays without a resistor as they will simply act as a direct short to ground.
 
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