I am trying to build a circuit for driving a seven segment display basically to count seconds. Now my doubt is I have purchased the following ICs a 555 timer, 4510 BCD up down counter, 4511 seven segment driver. i have read about different logic level standards like CMOS, TTL etc. So, do I need the ICs to be from the same family? Do I need to manually check on the IC whether it is from CMOS family or TTL or any other family? And for the 555 timer it is just written ne555p (11A3YRB) does it also belong to some logic family. It is the first time i am putting together all the hardware pieces together after simulation, So some help would get me going.
Small clarification, you are saying 4510 and 4511 is CMOS family and NE555 is TTL. So, when I interface these ICs from different families will it not create problem or do I need to make some interface logic between the TTL and CMOS?
Small clarification, you are saying 4510 and 4511 is CMOS family and NE555 is TTL. So, when I interface these ICs from different families will it not create problem or do I need to make some interface logic between the TTL and CMOS?
Hi Satya,
On the 3 types you have listed there will not be a compatibility problem.
There are problems when mixing CMOS and TTL logic, due the output voltage levels and input voltages not meeting the required specification of the 'other' family. Referred to as 'threshold' levels.