100+ System on Chip Multiple Choice Questions with Answers

The rapid advancement of semiconductor technology has led to the development of highly integrated electronic systems known as System on Chip (SoC). An SoC integrates multiple components of a complete electronic system—including processors, memory blocks, communication interfaces, peripherals, and specialized accelerators—onto a single silicon chip. This integration significantly reduces system size, power consumption, cost, and latency while improving performance and reliability.

Today, SoCs form the foundation of many modern technologies such as smartphones, IoT devices, automotive electronics, AI processors, wearable devices, networking equipment, and consumer electronics. Leading semiconductor companies design advanced SoCs that combine CPUs, GPUs, DSPs, NPUs, memory controllers, and high-speed communication interfaces within a single integrated circuit.

Because of this growing importance, understanding SoC architecture and design concepts has become essential for electronics and communication engineering (ECE) students, embedded system developers, VLSI engineers, and semiconductor professionals. Key topics in SoC design include processor architectures, on-chip communication protocols, memory hierarchy, power management techniques, clocking strategies, security mechanisms, verification methodologies, and advanced packaging technologies.

To help learners strengthen their understanding of these concepts, the following 100 multiple-choice questions (MCQs) on System on Chip (SoC) have been carefully designed. These questions cover a wide range of topics, including:

SoC architecture fundamentals
IP cores and reusable design blocks
On-chip communication protocols such as AMBA and AXI
Memory systems and cache hierarchy
Power optimization techniques like clock gating and DVFS
Design for testability (DFT) and verification methodologies
Network-on-Chip (NoC) architectures
Security mechanisms and hardware root of trust
Advanced SoC technologies such as chiplets and AI accelerators

Each MCQ includes four options, the correct answer, and a helpful hint, enabling readers to understand the reasoning behind the correct choice. These questions are suitable for exam preparation, interviews, competitive tests, and concept revision for students and professionals in the semiconductor domain.

1). What does SoC stand for?

System of Circuits

System on Chip

Silicon on Controller

Single Operating Circuit

2). The primary advantage of an SoC is?

Larger PCB size

Reduced power consumption

Increased wiring complexity

Higher external memory usage

3). Which processor architecture is most commonly used in SoCs?

x86

ARM

SPARC

MIPS

4). In SoC terminology, an IP core refers to?

Internet Protocol

Internal Processor

Intellectual Property core

Integrated Peripheral

5). Which of the following is NOT typically integrated in an SoC?

CPU

GPU

External Power Transformer

Memory Controller

6). AMBA is developed by?

Intel

AMD

ARM

IBM

7). Which bus protocol is used in high-performance SoCs?

I2C

SPI

AXI

UART

8). Cache memory in SoC improves?

Power dissipation

Latency

PCB size

Fabrication cost

9). Which memory is typically integrated on-chip?

DRAM

SRAM

Hard Disk

SSD

10). SoC integration reduces?

Performance

Signal delay

Functionality

Clock frequency

11). Which component in an SoC typically handles graphics processing?

DSP

GPU

DMA Controller

Timer

12). A DMA controller in an SoC is mainly used to?

Execute instructions

Transfer data between memory and peripherals without CPU intervention

Control clock frequency

Manage power domains

13). Which type of memory is usually used for cache in an SoC?

DRAM

SRAM

Flash

EEPROM

14). In an SoC, a bus arbiter is responsible for?

Memory storage

Controlling bus access among multiple masters

Increasing clock frequency

Reducing power

15). The main function of a memory controller in an SoC is to?

Execute CPU instructions

Manage data flow between processor and memory

Control display output

Perform encryption

16). In SoC architecture, a peripheral refers to?

External device connected through ports

Internal module providing specific functionality

CPU core

Power supply circuit

17). Which interface protocol is widely used for on-chip communication in SoCs?

AXI

USB

HDMI

Ethernet

18). In SoC design, latency refers to?

Power usage

Delay in data transfer or processing

Memory capacity

Clock stability

19). A watchdog timer in an SoC is used to?

Monitor system operation and reset if necessary

Increase processor speed

Control voltage supply

Increase memory size

20). The integration of multiple cores in an SoC enables?

Higher transistor leakage

Parallel processing

Reduced functionality

Larger PCB size

21). Which communication protocol is commonly used for connecting sensors in an SoC?

HDMI

I2C

VGA

PCIe

22). The main role of a timer module in an SoC is to?

Store large data

Generate time delays or periodic signals

Control GPU operations

Manage memory cache

23). UART communication in SoC is used for?

Parallel data transfer

Serial communication

Graphics processing

Cache management

24). An interrupt controller in SoC helps to?

Increase clock speed

Manage multiple interrupt signals

Store program instructions

Reduce chip area

25). Which unit in an SoC handles floating-point arithmetic?

ALU

FPU

DSP

Timer

System on Chip MCQs for Exams

26). In SoC design, scalability refers to?

Increasing chip thickness

Ability to add more cores or modules

Reducing transistor count

Lowering frequency

27). Which interface is commonly used for high-speed peripheral communication?

SPI

I2C

PCIe

UART

28). Boot ROM in an SoC is used to:

Store temporary data

Store initial boot code

Control display output

Manage network communication

29). Which component helps move data quickly between peripherals and memory?

DMA

GPU

Timer

Cache

30). The purpose of a PLL in an SoC is to?

Store program code

Generate stable clock signals

Perform encryption

Manage interrupts

31). In an SoC, a register file stores?

Large multimedia files

Temporary CPU data and instructions

Power supply values

Display signals

32). Which component accelerates signal processing tasks in SoC?

DSP

GPU

Timer

Cache

33). In an SoC, bus width determines?

Power supply

Amount of data transferred per cycle

Clock frequency

Memory latency

34). Which feature helps SoCs handle multimedia processing efficiently?

SRAM

DRAM

Flash

Cache

35). Which memory is non-volatile in an SoC?

SRAM

DRAM

Flash

Cache

36). Which SoC component manages external communication interfaces?

I/O controller

CPU pipeline

ALU

Cache

37). SoCs used in smartphones often integrate?

CPU only

CPU + GPU + DSP + modem

Only GPU

Only memory

38). In SoC design, integration reduces?

Power efficiency

Inter-chip communication delay

Functionality

Performance

39). A modem integrated in an SoC supports?

Graphics rendering

Wireless communication

Memory storage

Clock control

40). The primary role of a display controller in SoC is?

Manage graphical output to display devices

Control power supply

Increase CPU speed

Manage interrupts

41). Network-on-Chip (NoC) is used for?

External communication

On-chip interconnect

PCB routing

Power regulation

42). DVFS in SoC stands for?

Digital Voltage Frequency Scaling

Dynamic Voltage Frequency Scaling

Direct Voltage Fixed Scaling

Dual Voltage Frequency Structure

43). Power gating is mainly used to?

Increase clock speed

Reduce leakage power

Increase SRAM

Improve routing

44). Clock gating reduces?

Dynamic power

Leakage power

Memory size

Area

45). DFT in SoC means?

Design for Testing

Data Flow Transfer

Dynamic Frequency Timing

Design Flow Tree

46). Scan chains are used in?

Functional mode

Testing mode

Debug mode

Power mode

47). A heterogeneous SoC includes?

Single core CPU

Identical processors only

Different types of processors

Only GPU

48). A PLL in SoC is used for?

Memory storage

Clock generation

Debugging

Routing

49). Secure boot ensures?

Faster startup

Authentic firmware loading

Higher clock speed

Reduced area

50). In SoC verification, UVM stands for?

Unified Verification Methodology

Universal Validation Mode

Ultra Verification Mechanism

Unified Virtual Machine

System on Chip MCQs for Quiz

51). In SoC design, DVFS is used to?

Increase cache size

Adjust voltage and frequency dynamically

Reduce memory capacity

Improve routing

52). Power gating helps reduce?

Dynamic power

Leakage power

Cache size

Clock speed

53). Clock gating reduces?

Static power

Dynamic switching power

Chip area

Memory usage

54). Clock gating reduces?

Static power

Dynamic switching power

Chip area

Memory usage

55). Which SoC component routes packets in a Network-on-Chip?

Router

Timer

PLL

DMA

56). Multi-core SoCs mainly improve?

Sequential processing

Parallel computation

Memory latency

PCB size

57). The term heterogeneous computing refers to?

Identical processors only

Combination of different processing units

Single-core architecture

Only CPU usage

58). Cache coherency ensures?

Clock stability

Data consistency across cores

Higher voltage

Reduced memory size

59). Hardware accelerators in SoC are designed to?

Reduce power supply

Perform specialized computations faster

Increase transistor leakage

Replace memory

60). A secure enclave in an SoC protects?

Display output

Sensitive data and encryption keys

GPU rendering

Clock generation

61).Which protocol supports high-speed chip-to-chip communication?

PCIe

I2C

UART

SPI

62). SoC verification ensures?

Physical packaging

Correct functional behavior

Power supply stability

PCB thickness

63). Simulation in SoC design is used to?

Manufacture chips

Test functionality before fabrication

Reduce transistor count

Increase voltage

64). A common verification methodology for SoC is?

UVM

HTML

TCP

HTTP

65). Design partitioning in SoC helps to?

Increase power

Manage design complexity

Reduce functionality

Remove verification

66). Thermal sensors in SoC monitor?

Clock jitter

Chip temperature

Memory bandwidth

Bus arbitration

67). Hardware virtualization support in SoC enables?

Multiple operating systems

Higher voltage

Larger cache

Reduced frequency

68). Which component manages data encryption in secure SoCs?

Crypto engine

GPU

DMA

Timer

69). In modern SoCs, AI tasks are often handled by?

NPU

Timer

UART

Cache

70). SoC debugging during development is done using?

JTAG interface

HDMI port

Ethernet cable

VGA interface

71). Which technology improves power efficiency in mobile SoCs?

Big.LITTLE architecture

Single-core design

Fixed frequency clocks

Large PCB

72). Silicon interposers are used in?

2.5D packaging

Power supply circuits

Memory registers

Clock generation

73). A chiplet architecture divides a processor into?

Larger monolithic die

Smaller functional dies

Single transistor arrays

External components

74). Which issue occurs when signals cross asynchronous clock domains?

Power leakage

Metastability

Memory overflow

Cache miss

75). Which SoC component improves instruction execution speed?

Pipeline architecture

Timer

UART

Display controller

System on Chip MCQs for Interviews

76). Hardware redundancy in SoC improves?

Security

Fault tolerance

Clock speed

Power supply

77). Automotive SoCs require compliance with?

ISO 26262

HDMI

VGA

HTTP

78). Which SoC component handles video encoding/decoding?

Video codec engine

Timer

Cache

PLL

79). AI accelerators in SoC mainly improve?

Game rendering

Machine learning computations

Memory storage

Network cables

80). Future SoC architectures are increasingly focused on?

Single-core processors

Heterogeneous computing and AI integration

Larger PCBs

Lower transistor density

81). Which interconnect topology is commonly used in large SoCs?

Ring

Mesh

Star

Tree

82). Thermal management in SoC is critical because?

Chips are large

High transistor density

PCB thickness

External voltage

83). Chiplet architecture is used to?

Reduce transistor size

Combine multiple dies in a package

Increase cache

Reduce testing

84). Hardware accelerators in SoC are mainly used for?

Booting

AI/ML tasks

Printing

BIOS

85). Secure enclave in SoC protects?

Display

Sensitive data

Clock

GPU

86). FinFET technology helps SoC by?

Increasing leakage

Reducing short channel effects

Increasing PCB size

Slowing switching

87). Coherency protocol ensures?

Voltage stability

Cache consistency

Power gating

Memory size

88). Big.LITTLE architecture is designed for?

Area reduction

Performance-power optimization

Larger cache

Routing simplicity

89). AI SoCs typically include?

Only CPU

NPU

Only SRAM

Transformer

90). The major challenge in modern SoC design is?

Lack of transistors

Power and thermal constraints

PCB routing

Wire length outside chip

91). In multi-voltage SoC design, level shifters are required when?

Crossing clock domains

Crossing voltage domains

Crossing test modes

Crossing reset signals

92). Isolation cells in SoC are primarily used to?

Improve timing

Prevent floating signals during power gating

Increase clock frequency

Reduce routing congestion

93). Clock Domain Crossing (CDC) issues may result in?

Lower leakage

Metastability

Reduced area

Faster clock

94). Which technique is commonly used to mitigate metastability?

Buffer insertion

Synchronizer flip-flops

Larger cache

PLL tuning

95). In large SoCs, hierarchical design methodology is used to?

Increase power

Manage complexity

Reduce transistor count

Eliminate verification

96). High Bandwidth Memory (HBM) in SoC is typically connected using?

SPI

I2C

TSV (Through-Silicon Vias)

UART

97). EM (Electromigration) in SoC interconnects is caused by?

Low voltage

High current density

Slow clocks

Small area

98). IR drop analysis in SoC is performed to verify?

Routing density

Power integrity

Cache size

Test coverage

99). A common challenge in 5nm and below SoCs is?

Reduced performance

Increased short-channel effects

Larger die size

Lower integration

100). Chiplet-based SoC architectures improve yield by?

Increasing die size

Reducing clock frequency

Partitioning large die into smaller dies

Removing cache

101).Cache coherency in multi-core SoCs is maintained using?

UART protocol

MESI protocol

SPI protocol

I2C arbitration

102). A typical hardware root of trust in SoC is implemented using?

SRAM

ROM

Hard disk

DRAM

103). In advanced SoCs, PCIe controller is used for?

Low-speed communication

High-speed external connectivity

Internal memory access

Power control

104). Dynamic Thermal Management (DTM) in SoC adjusts?

PCB thickness

Clock frequency and voltage

SRAM size

Routing layers

105). A deadlock in Network-on-Chip (NoC) can occur due to?

High voltage

Circular resource dependency

Low cache

Fast clock

106). Formal verification in SoC design is mainly used to?

Improve routing

Prove functional correctness mathematically

Reduce clock speed

Optimize PCB

107). In advanced SoC packaging, 2.5D integration uses?

Standard PCB

Silicon interposer

Wire bonding only

Plastic substrate

108). Glitch power in SoC logic is caused by?

Stable signals

Unnecessary signal transitions

Power gating

SRAM access

109). Retention registers are used in SoC to?

Store debug logs

Preserve state during low-power modes

Increase frequency

Improve routing

110). The biggest architectural trend in modern SoCs for AI workloads is?

Single-core design

Increased CPU frequency only

Heterogeneous compute with dedicated accelerators

Larger PCB size