How to design (ROM) by using BJT Transistior ?

[Mahmoud90]

Hi,
My question is : How to design and implementation Read only memory (ROM) by using BJT
Transistor and store the date of birth for each student and the configuration to store it,
for example 25 – 10 – 95. And Then display it on 7-Segmants.

Here is some information about the question .. I need help please


Thanks in advance ..

Mahmoud

 

[godfreyl]

That's going to need lots of transistors. Did they tell you what dates to store, or can you choose? It sounds like there is help in chapter 32 of your textbook.

 

[Mahmoud90]

I just need the design, yeah there is help in the book but not enough !
The date will be like (22 04 98) in the 7-segmant , that's mean 22 of April 1998 ..

 

[godfreyl]

Here's one way to do it. I'm not going to draw the whole thing. This is just for 2 students and the first 7 segments.

Start with the circuit below, then delete the diodes you don't need.

 

[Mahmoud90]

Thanks alot for this design.. but the question is how to design it by BJT's, here I've the project after done, but I need the design for it .. the design worked by decoders because it's so simple than the number of BJT's .
so can you help me to get the design for the cct below?


Thanks in advance