Automotive PMIC applications, who is the strong player?

The market size of automotive Power Management IC (PMIC) chips is entering a period of rapid growth.

PMIC stands for Power Management Integrated Circuit, which is primarily responsible for providing stable and efficient power management functions for electronic devices.

In the electronic device system, the PMIC chip undertakes the transformation, distribution, detection, and other power management tasks of electrical energy, and is the heart of the power supply for all electronic devices. Its performance directly affects the energy consumption, performance, and reliability of the entire machine. If the PMIC fails, it will directly affect the operation of the electronic device and may even cause damage to the device itself.

Therefore, the role of PMIC is no less important than that of the MCU (Microcontroller Unit). It is the most widely used chip, and almost all electronic devices will have a PMIC.

01

PMIC applications in the automotive field

From the perspective of application fields, driven by electrification and automation, the in-vehicle field has become the fastest-growing area for the entire PMIC, with a compound annual growth rate of 9%.

Yole predicts that electric vehicles will account for 30% of the automotive market by 2026, and power management chips will further accelerate growth driven by electric vehicles. In addition, Yole also predicts that by 2026, all passenger cars and 80% of light commercial vehicles will be equipped with at least Level 1 ADAS, which also greatly increases the demand for multi-channel power management chips.

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Automotive-grade PMIC is the opportunity for domestic PMIC manufacturers.Innovative new electronic devices are fundamentally changing every aspect of vehicles, including the driving experience. Applications such as wireless connectivity, telematics, motor control, and safety features are continuously growing, all of which require power management for efficient and reliable operation.

The increasing popularity of hybrid and electric vehicles has further driven the development of the power semiconductor market. In hybrid and electric vehicles, there are many different power supply voltages, with varying output voltages, output currents, efficiency levels, and thermal ratings.

The many applications for electric or hybrid vehicles shown in the figure require varying degrees of voltage regulation. Most of these applications utilize a 12-volt or 24-volt power supply voltage, but some traction motor applications require higher voltages. All of these applications require effective buck, boost, or buck-boost conversion to achieve a variety of stable voltages throughout the vehicle.

Therefore, automotive power management integrated circuits (PMICs) are widely used in automotive intelligent cockpits, autonomous driving, body electronics, instrument and entertainment systems, lighting systems, and BMS, among other scenarios.

02

Automotive PMIC Application Requirements

Taking the PMIC in the front camera as an example, the front camera is an important component of the Advanced Driver Assistance System (ADAS), especially considering that current new car collision test requirements include automatic emergency braking and frontal collision avoidance as standard features of the vehicle. Automotive PMICs need to meet four major requirements to be successfully applied.

First, compact size solutions. High-resolution and higher frame rate camera modules are also developing trends. As the camera performance improves, the size of the camera module itself is also continuously shrinking, with a typical size of 18mm x 18mm. In addition, the visual processor in the camera has a dedicated hardware accelerator known as a visual processing accelerator. These processors may have artificial intelligence (AI) capabilities and are equipped with dedicated matrix multiplication accelerators to assist in deep learning. Considering such a large amount of processing, the PMIC must be able to meet the current requirements of the processor without increasing the size of the solution.

Second, functional safety. Since automatic emergency braking and adaptive cruise control involve the front camera, functional safety is particularly important. Front camera systems usually have Automotive Safety Integrity Level (ASIL) B requirements. This means that the PMIC power supply of the processor must be able to meet ASIL B requirements, thereby helping to achieve overall system-level functional safety requirements.

Third, low cost. It is expected that by 2028, the sales volume of front camera systems will exceed 70 million units, making it a common ADAS application in vehicles. Due to the widespread adoption of front cameras in passenger cars and light commercial vehicles, reducing the cost of the camera system is crucial.Fourthly, thermal performance. Since the front-facing camera is located on the vehicle's windshield, it is exposed to high temperatures under normal working conditions. Heat can cause thermal noise and lead to poor image quality. To adapt to various working conditions, optimizing the thermal performance of the system is crucial. The good thermal performance of the PMIC helps to keep the circuit board at a low temperature.

03

Automotive PMIC Solutions

Silead - High Integration Automotive Grade PMIC Chip TPU25401

Silead has released the TPU25401, specifically designed to power the main control SoC (System on Chip) in automotive intelligent cockpit and ADAS systems. It includes 5 buck converters, 5 linear regulators, with a total current output capability of over 22A. The output voltage can be dynamically adjusted from 0.6V to 3.7V, with an adjustment step of 10mV. The internal non-linear control provides a very fast dynamic load response speed, making it particularly suitable for core digital main chips such as SoC.

The flexible configuration features of Silead TPU25401 solve the drawbacks of traditional PMICs that can only adapt to a single platform SoC. According to feedback from SoC partners and related Tier1, TPU25401 can easily adapt to different platform SoCs in the automotive market.

Taking the intelligent cockpit SoC X9M platform of Xinchi as an example, only one TPU25401 is needed to meet all the power supply requirements of the system.

Silicon Power - Ultra-small PMIC Automotive Camera Solution SA47302

Silicon Power SA47302 is a power management solution developed based on automotive cameras, with a wide input voltage of 4.0V to 16V (ABS 18V). It consists of one main DCDC Buck regulator, two secondary DCDC Buck regulators, and a high PSRR low noise secondary LDO for sensor power supply, ensuring the stability and reliability of the power supply system.The power-up sequence of SA47302 is controlled by the high/low voltage level of the SEQ pin, supporting the power-up sequence of two power supply sequence buck converters and LDOs. When VIN (PVIN1) is powered up and VIN is higher than the VIN UVLO_H threshold, the Gate Drive LDO (VCC) of the main Buck converter is turned on, followed by the detection of the SEQ voltage level. When all channels have completed soft start and all channels output is stable, nReset is pulled high. When VIN is less than the VIN UVLO_F threshold, all outputs except VCC are powered down simultaneously. VCC remains on to maintain the normal operation of all gate drivers and internal logic until VIN drops below 3.6V, ensuring the safety and stability of the circuit.

Omnivision — Automotive Camera PMIC ORX1210

The ORX1210 is packaged in a QFN4x4mm2 and has a wide input voltage range of 4.0V to 18V. It consists of a mid-voltage DCDC Buck regulator, two low-voltage DCDC Buck regulators, and a high PSRR low-noise LDO.

The LDO is specifically optimized for the camera's sensitive frequency range (100K~1MHz), which can better suppress the impact of power supply noise on image quality. Flexible power-up sequence control ensures the stable operation of the system. It supports spread spectrum function, enhancing the system's EMI performance. High power efficiency and good thermal performance support the system to work normally at higher ambient temperatures. As the first camera power management chip in China to support functional safety ASIL B, it integrates a richer functional safety mechanism, and functional safety meets the ASIL B level requirements. Currently, this PMIC has been sent for sampling and will be mass-produced in Q4 of 2023.

Xinzhu Technology — Automotive Camera PMIC SCT61240Q

Xinzhu Technology currently has more than 10 automotive-grade power chip products online, including LDOs, buck converters, boost/buck-boost/flyback controllers, MOS tube drivers, power protection devices, and integrated PMIC products. It provides a full range of power solutions for various automotive applications such as intelligent cockpit/ADAS domain applications, automotive power domain, and body domain. Among them is the automotive camera PMIC SCT61240Q.

Due to the rich models of image sensors, their power architecture and timing requirements are also more diverse. To shorten the design time of engineers and speed up the product development cycle, PMIC should reduce peripheral components and simplify the design while also achieving flexible and adjustable output voltage and timing settings. The potential voltage drop problem of coaxial cables needs to be protected in time to avoid signal integrity issues. Overall, high integration, flexible control, and stable and reliable protection functions have become the core performance.

SCT61240Q has a wide voltage input range of 4-19V, including one mid-voltage DC/DC Buck, two low-voltage DC/DC Buck, and one high PSRR low-noise LDO. It can provide a complete power rail for automotive cameras. No matter what the design is, a single chip can cover the power supply needs and optimize system flexibility.SCT61240Q features a 2.5x3.5mm QFN-18L ultra-small package, eliminating the need for output voltage dividing resistors and pull-up resistors on the Power Good indicator pin, with a minimum of only 13 peripheral components required for stable operation, maximizing board space savings. It has a fixed switching frequency of 2.2MHz, supporting compact inductor design.

Torey Micro - Vehicle Camera Power Management Solution TMI7205B

The Torey Micro TMI7205B is a power management solution developed based on vehicle cameras, capable of generating all power rails for the imager and external circuits. The TMI7205B consists of three buck converters and one low-dropout (LDO) regulator, minimizing size and integrating multiple functions without compromising product performance, effectively utilizing space and optimizing the flexibility and thermal performance of the power system. Additionally, it has a wide input voltage range of 4.5V to 30V, greatly enhancing the stability of the power system.

The DC-DC operating frequency is designed at 2.3MHz, supporting compact inductor size and miniaturized design; meanwhile, the package adopts QFN4x4-24, further compacting the PCB layout and saving circuit area for the camera module; BUCK2 and BUCK3 operate in PFM mode during no-load and light-load conditions, effectively reducing power consumption, thereby optimizing the thermal management of the PMIC and module power supply; an integrated low-noise LDO is used, and BUCK operates in PWM mode under heavy load, solving the camera's ripple wave issue and improving image quality.

Conclusion

As a part of the independent and controllable automotive industry chain, the Ministry of Industry and Information Technology has set a development goal to increase the domestic chip localization rate to 20% by 2025, which has been actively responded to by many car companies. For example, Dongfeng Motor Group plans to increase the domestic localization rate of automotive-grade chips to 60% by 2025. The new changes in the automotive market are driving the rapid adoption of domestic chips, including PMICs.

Automotive-grade products require extremely high reliability and extremely low failure rates, which not only tests the design and R&D capabilities of chip companies but also their quality and supply chain management capabilities. Whether a company has automotive-grade products is a dividing line that distinguishes the capabilities of companies.Currently, domestic PMIC manufacturers mainly have two attitudes: one is to first do a good job with non-automotive grade products, and then consider automotive grade; the other is to insist on developing automotive-grade power management chips even if the current conditions are not particularly favorable. This is related to each company's R&D strength, technical reserves, and market strategy.

However, PMIC companies investing in the automotive market is becoming a global trend. The explosion of new energy vehicles is imminent, and domestic PMIC enterprises have ushered in the best window period for automotive-grade chip business.