Author Question: You are troubleshooting a TTL circuit board containing dozens of IC chips. You have taken several ... (Read 21 times)

Chelseaamend · **on:** Jul 27, 2018

You are troubleshooting a TTL circuit board containing dozens of IC chips. You have taken several readings at numerous IC chips but the readings are inconclusive because of their erratic nature. Assuming the circuit worked properly at one time, what is the most likely cause of the problem?

A) A solder bridge between the inputs on the first IC chip on the board
B) A defective output IC chip that has an internal open to Vcc
C) An open connection between the inputs on the first IC chip on the board
D) A defective IC chip that is drawing excessive current from the power supply

Question 2

A 74HC85 magnitude comparator is used to:

A) compare two input voltage levels and generate outputs to indicate which voltage has the greater magnitude.
B) Exclusive OR two binary quantities and generate an output if they are unequal in magnitude.
C) compare two input binary quantities and generate outputs to indicate which quantity has the greater magnitude.
D) AND two binary quantities and generate outputs only if they are equal in magnitude.