Depending on where they are installed, automotive CMOS image sensor (CIS) chips fall into two broad application areas: outside the cabin and inside the cabin.

1. Exterior image sensors

(1) Forward perception CIS. Forward perception CIS is mounted mainly on the windscreen and supports forward collision warning, lane departure warning, traffic sign recognition and pedestrian collision warning. One to three units are installed, corresponding to monocular, binocular and trinocular configurations, providing a wider field of view, deeper perception and high dynamic range. A trinocular setup, for example, combines a wide, a main and a narrow forward field of view with different HFOV lenses. Multi camera setups can be integrated on the windscreen or split so that one camera stays behind the windscreen while two are mounted on the roof rails outside, increasing the viewing angle and preventing nearby vehicles from blocking pedestrians and obstacles.

Technical parameters:

· Resolution: up to 8 MP, typically 2 MP or 1 MP
· High dynamic range: typically 120 dB, up to 140 dB
· LED flicker mitigation
· ISO 26262 functional safety

(2) Surround view CIS. Surround view CIS is mounted near the front and rear badges and integrated into the left and right mirrors, with four units providing a 360 degree surround view system and the basis for automated parking. A surround view system typically uses four to six high dynamic range, high resolution sensors distributed at the front, rear and both sides of the vehicle. The four sensors capture the corresponding images, and an algorithm projects them onto the central display as a bird's eye view covering the area around the vehicle. Beyond surround view, underbody transparency imaging has been proposed as a differentiated feature for safer automated parking.

Technical parameters:

· Resolution: up to 3 MP, typically 2 MP or 1 MP
· High dynamic range: typically 120 dB
· LED flicker mitigation
· On-chip ISP processing with YUV output
· ISO 26262 functional safety
· Good low light night vision performance

(3) Rear view CIS. Rear view CIS is mounted in the tailgate and displays a reversing image to assist parking. Like surround view, it usually consists of one high dynamic range, relatively high resolution sensor that captures the image and transmits it to the central display.

Technical parameters:

· Resolution: up to 2 MP, typically 1 MP or VGA
· High dynamic range: typically 120 dB
· On-chip ISP processing with YUV output
· Good low light night vision performance

(4) Side perception CIS. Side perception CIS is mounted below the mirrors for blind spot monitoring, also known as lane change assist. Its main function is to eliminate the blind spot behind the mirrors by detecting overtaking vehicles on both sides. When a vehicle enters the blind spot, the system alerts the driver with sound and light, protecting the vehicle during lane changes and turns and avoiding scrapes. Two units are typically installed.

Technical parameters:

· Resolution: up to 3 MP, typically 2 MP
· High dynamic range: typically 120 dB
· LED flicker mitigation
· ISO 26262 functional safety
· Good low light night vision performance

(5) Streaming and electronic mirror CIS. Streaming mirror CIS projects images from sensors on both sides and at the rear onto the display of the interior mirror in digital form, in contrast to a conventional optical mirror. The image is transmitted losslessly and without delay, recorded and displayed simultaneously, and provides glare suppression, low light compensation, rain and fog penetration, an ultra wide field of view and elimination of blind spots. Electronic mirrors replace the conventional exterior optical mirrors with a combination of automotive CIS and display devices, providing more image information and allowing a specific area to be observed closely, while being less affected by weather and surroundings.

Technical parameters:

· Resolution: up to 3 MP, typically 2 MP
· High dynamic range: typically 120 dB
· LED flicker mitigation
· ISO 26262 functional safety
· Good low light night vision performance

(6) Dash camera CIS. Dash camera CIS is mounted on the windscreen to capture vehicle speed, time and surrounding traffic and to record them automatically to storage. Analysis of the recorded material can confirm driver behaviour and support accident prevention and safety management. Dash camera designs are often integrated with the streaming mirror or a forward facing all-in-one unit, and there are many variants. Dash cameras also have a substantial aftermarket.

Technical parameters:

· Resolution: mainly 1 MP
· High dynamic range: typically 120 dB
· On-chip ISP processing with YUV output
· Good low light night vision performance

2. Interior image sensor chips

(1) Driver monitoring CIS. Driver monitoring CIS is mostly mounted on the interior mirror, the headliner directly above the driver or the A-pillar, or hidden between the steering wheel and the instrument panel, to monitor driver state and provide fatigue alerts. One unit is typically installed. With policy support for commercial passenger and hazardous goods transport, driver monitoring has become standard on commercial vehicles and is spreading to passenger cars.

Technical parameters:

· Resolution: mainly 1 MP, up to 2 MP
· Global shutter
· Relatively high dynamic range
· ISO 26262 functional safety
· Good low light night vision performance

(2) Occupant monitoring CIS. Occupant monitoring extends driver monitoring to the whole interior. One unit is typically installed to detect the front passenger, rear occupants and left items, including seat belt use, occupant posture and occupant count, and in particular to detect and remind about items or children left behind after the driver leaves, protecting personal and property safety.

Technical parameters:

· Resolution: mainly 1 MP, up to 5 MP
· RGBIR optical filter
· Relatively high dynamic range
· Good low light night vision performance

3. Development of domestic image sensor chips

Image sensor chips are currently dominated by major international suppliers, leaving substantial room for domestic chips. The image sensor is the highest value element of an automotive camera and has high technical barriers. The market is basically held by onsemi, OmniVision and Sony, and import substitution in China is only at an early stage.

Domestic image sensor suppliers

4. AEC-Q100 qualification required for automotive image sensor chips

1. AEC-Q certification is the entry threshold for automotive electronics. AEC stands for Automotive Electronics Council. It was founded in 1994 by Chrysler, Ford and General Motors, and its membership now spans major vehicle makers, automotive electronics companies and semiconductor manufacturers worldwide. Components that comply with AEC specifications can be adopted by all three manufacturers at the same time, which encouraged part makers to exchange product characteristic data, drove standardisation of automotive parts and laid the foundation for the rapid growth of the automotive parts market. AEC-Q is the automotive reliability test standard issued by the AEC and an important passport for part makers entering automotive electronics and tier one supply chains.

AEC-Q100 was the first AEC standard, a set of stress test specifications designed for integrated circuits in automotive applications. It is important for improving product reliability and quality assurance. AEC-Q100 confirms the quality and reliability of each chip against possible conditions and latent failure states, with standardised tests of product function and performance in particular.

2. Automotive ICs required to pass AEC-Q100. Single chip ICs: control, driver, computing, memory, sensor, communication, power, power supply, security and analogue chips.

3. AEC-Q100 operating temperature grades for integrated circuits.

▸ Grade 0: ambient operating temperature -40℃ to 150℃
▸ Grade 1: ambient operating temperature -40℃ to 125℃
▸ Grade 2: ambient operating temperature -40℃ to 105℃
▸ Grade 3: ambient operating temperature -40℃ to 85℃

4. AEC-Q100 validation flow for automotive IC products.

5. AEC-Q100 test groups.

Group A, accelerated environmental stress tests (PC, THB/HAST, AC or UHAST or TH, TC, PTC, HTSL): 6 tests
Group B, accelerated lifecycle simulation (HTOL, ELFR, EDR): 3 tests
Group C, package assembly integrity (WBS, WBP, SD, PD, SBS, LI, BST): 7 tests
Group D, die fabrication reliability (EM, TDDB, HCI, BTI, SM): 5 tests
Group E, electrical verification (TEST, HBM, CDM, LU, ED, FG, CHAR, EMC, SC, SER, LF): 11 tests
Group F, defect screening (PAT, SBA): 2 tests
Group G, cavity package integrity (MS, VFV, CA, GFL, DROP, LT, DS, IWV): 8 tests

6. NTEK chip testing capability and AEC-Q100 requirements.

About NTEK

NTEK Group was founded in 2009 and is headquartered in Shenzhen. The group provides quality research and technical services covering R&D verification, inspection and testing, failure analysis, simulation and market access for intelligent connected vehicles, electronic communications and new energy.

NTEK has extensive experience in automotive-grade electronic certification and has helped more than 100 companies pass AEC-Q series certification, confirming the quality and reliability of each chip case against AEC-Q100.

Driven by the need of vehicle makers to localise automotive-grade chips and supported by the domestic semiconductor industry, NTEK provides comprehensive testing and certification services, applying AEC-Q100 automotive standards to control the safety and quality of automotive chips, supporting the growth of domestic automotive-grade chips and adding new momentum to the intelligent vehicle safety system.