Chapter 4 - Combinational Logic Circuits True or False Questions
A combination logic circuit has memory characteristics that "remembers" the inputs after they have been removed.
False
A good rule of thumb for determining the pin numbers of a DIP (dual-in-line package) IC chip would be to place the notch to your right and pin #1 will always be in the lower right corner.
False
Digital voltmeters can be used to troubleshoot a digital circuit.
False
It can be worse to leave TTL inputs floating than CMOS.
False
It is acceptable in a TTL based design to leave unused inputs floating.
False
Karnaugh maps reduce Boolean equations further than using algebraic simplification.
False
Schematics show how mechanical components connect in a circuit.
False
Single looping in groups of 3 is a common Karnaugh map simplification technique.
False
TTL stands for transistor-technology-logic.
False
When labeling a Karnaugh map, it makes no difference if adjacent vertical and horizontal squares differ in more than one variable since the end result will be correct.
False
A Karnaugh map lists the value for each possible combination of input values.
True
A logic probe is a device that can be used to troubleshoot digital circuits.
True
A square in the top row of a Karnaugh map is considered to be adjacent to its corresponding square in the bottom view.
True
An inverter gate can be used just like an AND, OR, NAND and NOR to control or inhibit logic signals from passing to their outputs.
True
Generally speaking, when the non-inverting AND & OR gates are used to enable signals, the output signal will follow the desired input signal exactly.
True
In true sum-of-products expressions, the inversion sign cannot cover more than single variables in a term.
True
Karnaugh maps are just a graphical representation of the same information that can be found in a truth table.
True
Karnaugh maps many times reduce Boolean equations FASTER than using algebraic simplification methods.
True
One characteristic of an Exclusive OR gate is that it can be used as a controlled inverter.
True
One of the primary steps in algebraic circuit simplification is to put the original expression into the sum-of-products form by repeated application of DeMorgan's theorems and multiplication of terms.
True
Oscilloscopes can be used to troubleshoot digital circuits.
True
Shorted signal lines can be tested using an ohmmeter for continuity.
True
TTL is the most widely used family of BIPOLAR IC's.
True
The 4000 series of digital parts is the oldest CMOS series around.
True
The 54 prefix on IC's indicates a broader operating temperature range, generally intended for military use.
True
The AND gate is an example of combination logic.
True
The Karnaugh map provides a "cookbook" approach to simplifying Boolean expressions.
True
The abbreviation for an exclusive-OR gate is XOR.
True
The expression /(AB) and /A + /B are equivalent.
True
When troubleshooting a digital circuit, it is good to start by verifying the power supply voltages.
True
