Need help building a Digital Cricket Scoreboard from scratch

Ian0

Joined Aug 7, 2020
6,698
Thanks @Ian0 if you look at my sketch. where do I end using the 2N7000? Not sure where I would connect them. Are you able to mark up my sketch. Thanks very much
gate goes to the segment outputs on the 40110
source goes to 0V
drain goes to the negative terminal of the LED segment.
positive terminal of the LED segment goes to 12V
 

dl324

Joined Mar 30, 2015
15,446
To be honest, I couldn't follow the above as I'm not really an electronics wiz. I can follow to schematics to a certain extent.
What is there to follow? There's a decade counter with 10 outputs that select the digits. Your original post showed 9 digits and a subsequent showed 10; 10 digits can be accommodated with the same chip. Then there's an OR gate to allow the program to reset the counter and a BCD to seven segment decoder.

What I showed is essentially the whole circuit. For 10 digits: 3 5 IC's, 17 transistors, 3 switches, some caps, some resistors, something like an Arduino Uno/Nano, and your LEDs.

Do you realize that, if you continue to go down the path you're on, you're going to need 10 CD40110? That's why several members have suggested a microcontroller. With those counters, you're going to need 700 70 transistors to drive the segments.

EDIT:
There are 10 displays so total of 70 modules. Modules I'm using is 12VDC & 0.7W each. So around 5amps current.
I'm planning on using 12V 10amp Power supply unit.
If you multiplex the digits, you can reduce the power requirement because only one would be on at a time; but you'll operate them at a higher current to compensate for being multiplexed.

For the circuit I posted, you'll also need a 5V regulator and a couple quad level shifters (CD40109) to shift the 4511 outputs to 12V.
clipimage.jpg

EDIT2: Changed IC count, corrected typo on transistor count when using CD40110, and attached an updated schematic:
clipimage.jpg
There are 7 P channel MOSFETs and 7 pull up resistors in the display box.
 
Last edited:

Ian0

Joined Aug 7, 2020
6,698
Do you realize that, if you continue to go down the path you're on, you're going to need 10 CD40110? That's why several members have suggested a microcontroller. With those counters, you're going to need 700 transistors to drive the segments.
By my calculations 10 digits x 7 segments = 70 transistors.
 

Ian0

Joined Aug 7, 2020
6,698
What is there to follow? There's a decade counter with 10 outputs that select the digits. Your original post showed 9 digits and a subsequent showed 10; 10 digits can be accommodated with the same chip. Then there's an OR gate to allow the program to reset the counter and a BCD to seven segment decoder.

What I showed is essentially the whole circuit. For 10 digits: 3 5 IC's, 17 transistors, 3 switches, some caps, some resistors, something like an Arduino Uno/Nano, and your LEDs.

Do you realize that, if you continue to go down the path you're on, you're going to need 10 CD40110? That's why several members have suggested a microcontroller. With those counters, you're going to need 700 70 transistors to drive the segments.

EDIT:
If you multiplex the digits, you can reduce the power requirement because only one would be on at a time; but you'll operate them at a higher current to compensate for being multiplexed.

For the circuit I posted, you'll also need a 5V regulator and a couple quad level shifters (CD40109) to shift the 4511 outputs to 12V.
View attachment 220936

EDIT2: Changed IC count, corrected typo on transistor count when using CD40110, and attached an updated schematic:
View attachment 220946
There are 7 P channel MOSFETs and 7 pull up resistors in the display box.
The maximum output current of a 40109 is 6.8mA, divide that by 9 for the multiplex gives 755uA, and you're expecting that to be visible in bright sunlight at a distance of 100 yards? Really? Where are you getting your LEDs?
 

Ian0

Joined Aug 7, 2020
6,698
Update: If the LEDs are only 0.7W at 12V then you can drive a whole-digit's worth with a ULN2003 instead of seven 2N7000 MOSFETs.
 
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