74LS192 counter problem

Thread Starter

yousef essam

Joined Sep 23, 2019
1
Guys I am using a 74LS192 BCD counter in a project. I have one problem that seems to exist in all different 6 counter ICs I bought
Qb which is the second output when high gives only 0.94V while other output pins give 2V. The 0.94V doesn’t translate to High in the 7segment decoder I use. Can anybody help please
 

danadak

Joined Mar 10, 2018
3,712
Wiring error between decoder output connected to Qb ? Or decoder
input for Qb is trashed. Later just disconnect Qb from it and see if it
achieves a logic "1".


Regards, Dana.
 

Reloadron

Joined Jan 15, 2015
4,724
Guys I am using a 74LS192 BCD counter in a project. I have one problem that seems to exist in all different 6 counter ICs I bought
Qb which is the second output when high gives only 0.94V while other output pins give 2V. The 0.94V doesn’t translate to High in the 7segment decoder I use. Can anybody help please
This is the data sheet for your counter, a 74192 PRESETTABLE BCD/DECADE UP/DOWN COUNTER. Output High should be a minimum of 2.7 Vol;ts and not the 2.0 V you mention. My guess is there is more going on than just the Qb being low. This is where, as suggested, a schematic would go a long way.

Ron
 

dl324

Joined Mar 30, 2015
9,332
Guys I am using a 74LS192 BCD counter in a project. I have one problem that seems to exist in all different 6 counter ICs I bought
Qb which is the second output when high gives only 0.94V while other output pins give 2V.
Where did you purchase these chips? None of the voltages you mention are within the specs:
upload_2019-9-23_8-35-24.png
upload_2019-9-23_8-32-6.png
upload_2019-9-23_8-32-32.png

What are the outputs driving for those measurements?
 
Top