What is the primary function of a decoder in digital circuits?
A Store data
B Convert binary to decimal
C Perform logical operations
D Activate one output based on input
A decoder takes a binary input and activates the corresponding output line based on that input. For example, a 2-to-4 decoder activates one of four outputs depending on the 2-bit input.
What type of circuit is used to add binary numbers?
A Adder
B ALU
C Decoder
D Register
An adder is a digital circuit used for performing addition of binary numbers. It can be a half-adder or a full-adder, depending on whether it handles carry inputs.
What does a finite state machine (FSM) represent in digital systems?
A Memory storage
B Data conversion
C A sequence of operations
D Logic operations
A finite state machine (FSM) represents a system that transitions between a finite number of states based on inputs and previous states. It controls the flow of operations in digital systems like controllers.
Which type of circuit performs logical operations such as AND, OR, and NOT?
A Encoder
B Combinational
C Flip-flop
D Sequential
Combinational circuits perform operations based solely on current inputs without any memory. Examples include logic gates like AND, OR, and NOT, which are used for performing basic logical functions.
Which of these is an arithmetic operation performed by an ALU?
A Encoding
B Counting
C Addition
D Storing data
An ALU (Arithmetic Logic Unit) performs arithmetic operations such as addition, subtraction, multiplication, and division. It also performs logical operations like AND, OR, and NOT.
What is the primary characteristic of a sequential circuit?
A Synchronous timing
B Logic operations
C Based on inputs
D Memory storage
A sequential circuit has memory, meaning its output depends on both the current input and its previous state. This allows the circuit to store data and is used in flip-flops and counters.
What type of memory is used to store permanent data in digital systems?
A ROM
B Cache
C Flash
D RAM
ROM (Read-Only Memory) is non-volatile and used to store permanent data, such as firmware or boot instructions, that does not change and needs to be preserved even when power is turned off.
What is the function of a 4-to-2 encoder?
A Selects one output from multiple inputs
B Stores data
C Converts multiple inputs to binary
D Converts binary to decimal
A 4-to-2 encoder takes 4 input lines and converts them into a 2-bit binary code that represents the active input. It is used to reduce the number of data lines in communication systems.
Which gate outputs 1 only when inputs are different?
A OR
B NOT
C AND
D XOR
An XOR (Exclusive OR) gate outputs 1 when the inputs are different. If one input is 0 and the other is 1, the output is 1; if both inputs are the same, the output is 0.
What does a flip-flop store?
A Binary data
B Program instructions
C Memory addresses
D Decimal values
A flip-flop is a bistable device used to store one bit of binary data. It has two states, and it switches between them based on clock signals and input conditions, making it essential for data storage in digital circuits.
Which circuit is used to store and shift binary data?
A Counter
B Decoder
C Shift register
D ALU
A shift register is used to store binary data and shift it in one or both directions (left or right) with each clock pulse. It is commonly used for data storage, data transfer, and digital signal processing.
What does a 3-to-8 decoder do?
A Selects one of several inputs
B Activates one of eight outputs based on input
C Converts decimal to binary
D Performs addition
A 3-to-8 decoder takes 3 binary input bits and activates one of 8 output lines. Each output corresponds to a different combination of the 3 input bits, allowing efficient data routing and addressing.
What is the function of a clock signal in a digital system?
A Store data
B Decode instructions
C Ensure correct synchronization
D Shift data
A clock signal provides timing for digital circuits, ensuring that operations like state transitions in flip-flops and registers occur at precise intervals. It helps synchronize different components in a system.
What is the key feature of an ALU?
A Signal routing
B Arithmetic and logical operations
C Data storage
D Memory addressing
An ALU (Arithmetic Logic Unit) performs both arithmetic operations, like addition and subtraction, and logical operations, such as AND, OR, and NOT, in a digital system.
What is the primary purpose of a state machine in digital electronics?
A Store data
B Control state transitions based on inputs
C Perform mathematical operations
D Perform data conversion
A state machine, like a finite state machine (FSM), controls the transition between different states based on input conditions. It is used in control systems, data processing, and digital controllers to manage sequential operations.