How much do you know about the IC chips in smartphones?

Table of Contents

• CPU & Multi-core Evolution
• GPU & Graphics Processing
• NPU & AI Computing
• PMIC & Power Management
• Memory & Caching
• Sensor Interface Chips
• Role of the PCB
• Conclusion

CPU & Multi-core Evolution

Since the first iPhone in 2007 used a single-core ARM11 processor, mobile CPUs have undergone numerous architectural upgrades. ARM’s Cortex-A series, celebrated for its power efficiency, became mainstream. In 2013, the introduction of the big.LITTLE architecture achieved a dynamic balance between performance and power by pairing “big” and “LITTLE” cores. Flagship SoCs in 2025 are expected to integrate 8–10 CPU cores, with “super-big” cores pushing beyond 3.5 GHz clock speeds, further boosting single- and multi-thread performance.

Technically, chipmakers optimize instruction pipelines through superscalar designs, out-of-order execution, and branch prediction. Advanced process nodes (e.g., 3 nm, 4 nm) and new transistor structures (FinFET, GAAFET) dramatically reduce power consumption and heat, ensuring stable performance under heavy loads.

Qualcomm’s Snapdragon 8 Gen 3, for example, adopts a tri-cluster design with one Cortex-X4 “super-big” core, three Cortex-A720 “big” cores, and four efficiency cores. Its smart scheduling engine dynamically allocates workloads—calling on the big cores for gaming or video rendering, while leaving light tasks to the efficiency cores to extend battery life.

GPU & Graphics Processing

The mobile GPU handles graphics rendering, video encoding/decoding, and AI-acceleration tasks. High-end mobile processors now feature thousands of arithmetic logic units (ALUs). For instance, the Adreno 750 in Snapdragon 8 Gen 3 sports 1,536 ALUs and supports Vulkan ray tracing and 8K HDR video decoding. Hardware codecs (HEVC, AV1) combined with dynamic voltage and frequency scaling (DVFS) cut power draw by over 30%. Apple’s A17 Pro integrates dedicated ray-tracing units and an AI super-resolution engine, delivering real-time dynamic shadows and global illumination for significantly enhanced graphics.

NPU & AI Computing

NPUs leverage sparse computation and quantization-acceleration techniques to deliver 10–50 TOPS (INT8) of inference throughput, achieving energy efficiency beyond 1 TOPS/W. Chipmakers provide compiler toolchains (e.g., TensorRT Mobile) that optimize layer fusion and operator scheduling to further boost performance. MediaTek’s Dimensity 9200, for example, features an APU 690 with mixed-precision support (INT4 + FP16) and on-chip memory compression, elevating AI efficiency by 35% over previous generations.

PMIC & Power Management

PMICs employ multi-phase digital buck converters (e.g., 6-phase CPU power delivery) and adaptive gate drivers, achieving >95% power-conversion efficiency. Fast-charging ICs integrate GaN switches and charge-pump circuits to support up to 200 W direct charging (20 V/10 A), filling a battery to 80% in just 10 minutes. PMICs communicate with the SoC via SMBus for real-time voltage-offset calibration, ensuring stable, reliable power delivery.

Memory & Caching

LPDDR5X memory introduces Bank Group Refresh (BGR) to cut standby power. UFS 4.0 storage, leveraging the M-PHY 5.0 interface and Host Performance Booster 2.0, boosts random read/write performance by up to 60%. Samsung’s V-NAND 3D flash uses Toggle 4.0 and RPMB partitions for encryption and wear leveling, enhancing both security and lifespan.

Sensor Interface Chips

Beyond core compute units, smartphones include various sensors—camera ISPs, touch controllers, accelerometers, and gyroscope interfaces. These dedicated SoCs or DSPs handle data acquisition, preprocessing, and protocol decoding, transmitting sensor data over I²C, SPI, or MIPI CSI buses to the main processor.

High-performance ISPs can preprocess 4K 60 fps RAW video, support HDR and noise-reduction algorithms, and feed AI pipelines with high-quality inputs. Touch controllers offer multi-touch pressure sensing and gesture detection, enhancing user responsiveness.

The Role of the PCB in IC Collaboration

Although secondary in function, the PCB is indispensable as the physical substrate for IC signals and power. Advanced HDI boards and embedded passives enable ultra-thin designs in the AIoT era, accommodating more chips. Thoughtful routing, ground-plane isolation, and differential-pair layouts maintain signal integrity on high-speed interfaces (USB4, PCIe, LPDDR5).

Proper division of power and ground layers, coupled with EMI-shielding structures, minimizes interference and boosts RF performance and stability. In high-frequency environments, the PCB—while “secondary”—is critical for interconnection and IC collaboration.

• For a deep dive into PCB best practices, see our blog: How to Properly Design Your PCB

Conclusion

From CPUs, GPUs, and NPUs to PMICs, memory, and sensor interfaces, each IC performs a unique role, collectively forming the smartphone’s “brain.” A deep understanding of these chips’ characteristics, performance metrics, and interplay helps consumers and developers make informed choices and optimizations.

Meanwhile, treating PCB design as a supporting factor ensures that IC performance can be fully realized. As more dedicated chips and heterogeneous compute units emerge, the IC ecosystem will further diversify, delivering ever-richer and smarter smartphone experiences.