display 4 digits using two 7 segment displays

Thread Starter

Mario Emad

Joined Feb 17, 2009
2
The first thing will be to check the datasheet for the pinout and whether it's common-anode or common-cathode.

Then you need to know how much the max. current for each LED, and you can go from there to determine if or what size of external resistor you will need for each LED.
Assuming that it's Common Anode, and I want to display a 4-bit no.(with switches) on two 7-segment displays , how?
 

beenthere

Joined Apr 20, 2004
15,819
You are urged to always start a new thread with each question. Placing your topic in an existing thread can be confusing.

This is the old thread - http://forum.allaboutcircuits.com/showthread.php?t=15473.

As in things electronic, there are always more than one way to get there. The hard way would be to use 14 SPDT switches and switch betenn two pairs of drivers. Another way is to use multiple pole rotart switches and shift the source of the data to one pair of decoders.

We have no idea of the arrangement of elements in your circuit, so a sensible answer becomes difficult. What is the circuit? Is it multiplexed? Is there a reason why adding two more displays is not possible?
 
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