TI, Toshiba, Spreadtrum in-vehicle smart rearview mirror design solution

   As the link between the Internet, Internet of Vehicles and Internet of Things, the car smart rearview mirror closely combines the three, bringing more safety, entertainment and intelligent application experience to the driving life of many car users. Car smart rearview mirrors will gradually become an indispensable part of Volkswagen's automotive products.

　　Currently, the smart rearview mirrors on the market have independent operating systems and independent running spaces. Users can install software, games, navigation and other programs provided by third-party service providers by themselves, and can achieve wireless network access through WIFI or mobile communication networks. At the same time, they can provide voice control, navigation, speeding reminders, driving records, GPS positioning, electronic speed reminders, reversing visualization, real-time online audio-visual entertainment and other safety and entertainment functions while driving a car.

　　Smart rearview mirrors are a new type of recorder product that has only emerged in the past two years. Their development has been short-lived but rapid. Well-known domestic companies such as Xiaoyi, Dingdong, and Zhixing Changlian have all launched their own smart rearview mirrors with OBD functions, which use the OBD standard interface to draw power, obtain data, and realize parking monitoring functions. At the 2016 International Automotive Electronics Modification Exhibition, 85% of the area was occupied by smart rearview mirror products. ADAS, front and rear dual recording, smart voice, gesture control and other black technologies are integrated in the smart rearview mirror, turning it into a perfect smart robot form in the car.

　　Smart rearview mirrors generally have to pass tests under extreme conditions, such as temperature, continuous vibration, etc. Extremely low or high temperatures will cause them to not work properly. So what functions do smart rearview mirrors generally have?

　　1. Driving record: the smart rearview mirror uses the built-in camera or the additional camera to record the images in front and behind the vehicle during driving, and automatically saves them in a loop in the storage device of the smart rearview mirror.

　　2. Speeding reminder: The navigation software in the smart rearview mirror operating system generally has a built-in fixed electronic speed reminder. Some smart rearview mirrors are equipped with radar detection heads that can detect mobile speed measurement in real time and sound an alarm to prevent the car from speeding and ensure safe driving at all times.

　　3. Reversing is visible. Reversing with the rearview mirror is safer than watching the car screen. After the smart rearview mirror is equipped with a reversing camera, the image behind the car can be displayed when reversing.

　　4. GPS positioning navigation: after real-time positioning by GPS, Beidou satellite or network, you can use pre-installed navigation application software such as Baidu Maps, AutoNavi or Carlead Navigation to achieve navigation, and voice broadcast navigation information. After connecting to the network, you can also broadcast real-time traffic conditions to avoid congestion.

　　5. Find the location of the car - the navigation function in the smart rearview mirror. The smart rearview mirror uses GPS, Beidou satellite or network positioning to obtain the exact location of the car. On an authorized smartphone or tablet, after connecting to the network, you can use a special application software to find the location of the car.

　　6. Based on the support of the network voice command library, the operating system in the smart rearview mirror can accurately analyze the user's voice commands and respond to them, realizing intelligent voice dialogue between people and cars. It can recognize voice commands such as "make a call, open an application, play music, and voice chat".

　　7. Bluetooth hands-free phone, smart rearview mirror is compatible with smart phones, synchronizing mobile phone contacts and call records; realizing the functions of answering, hanging up and do not disturb calls; it can also realize intercom with car friends and synchronize mobile phone music playback with Bluetooth; built-in 3G network module, share wireless network, online music and listen to news information with friends in the car through wifi; install life and entertainment applications such as WeChat, Weibo, Taobao mobile, Alipay, Himalaya, NetEase client, Tencent client, etc.

　　Here are some automotive smart rearview mirror design solutions from Toshiba, Texas Instruments, and Spreadtrum.

　　1. BLE car rearview mirror solution based on TI  CC2541

　　This reference design is an example of applying the SimpleLink™ Bluetooth low energy CC2541 wireless microcontroller to a car rearview mirror application. Its circuit board includes CC2541 controlling DRV8801 to control the rearview mirror folding motor, controlling DRV8802 to control the rearview mirror up and down and left and right adjustment motor, and controlling TPS1H100 to control the defogger heater power supply. That is, the user can issue a rearview mirror action command to the CC2541 BLE chip through a smartphone app, and then CC2541 will convey the command to the DRV8801/DRV8802/TPS1H100 and other functional chips, which will then act according to the action conditions set by the user.

　　【Application scenarios】

　　【Solution diagram】

　　【Solution Features】

　　(1) Use the TI  CC2541 module to set the rearview mirror actuation function conditions

　　(2) The power supply uses LM2936 LDO to power the system, and TPS55340 to power the motor driver.

　　(3) The motor is driven by DRV8801 / DRV8802

　　(4) The defog function is performed by TPS1H100

　　(5) Older models can add this function by simply replacing the rearview mirror with an electric control function and completing the power wiring.

　　【System functions】

　　(1) The vehicle battery provides 10~24V DC power supply

　　(2) The DC power supply provides stable power to DRV8801 / DRV8802 through TPS55340

　　(3) DC power is supplied to CC2541 and LMV341 via LM2936 LDO

　　(4)  TI  BLE Mul TI tool Remote Control APP for Android

　　(5) CC2541 controls DRV8801 to fold and close the rearview mirror according to APP instructions

　　(6) CC2541 controls DRV8802 to adjust the rearview mirror up, down, left, and right according to APP instructions

　　(7) CC2541 controls TPS1H100 to perform rearview mirror defog function according to APP instructions

　　2. Car rearview mirror solution based on Spreadtrum SC7731

　　Since its birth, the rearview mirror in the car has basically become a forgotten corner due to its single function. Recently, a well-known car manufacturer plans to make the rearview mirror a standard feature in 2016. It is the first time that the car manufacturer has paid attention to the rearview mirror. Is this a signal that the car manufacturer will gradually turn the physical rearview mirror into an in-vehicle electronic component with a multifunctional combination?

　　The car rearview mirror has added driving records, electronic dog, navigation, and rear-view functions without affecting the basic functions. It is easy to install and does not need to dismantle the original car audio and video equipment, and will not change the original car style. It has the characteristics of easy installation, strong versatility, easy upgrade, and strong extensibility. This is also the reason why the car rearview mirror has been so popular in recent years.

　　Car rearview mirrors are about to become the new darling of the future automobile market. World Peace Group has also joined hands with IDH Duoyue to launch a car rearview mirror solution based on Spreadtrum SC7731.

　　【Solution diagram】

　　【System functions】

　　Running Android

　　GSM/GPRS/EDGE/WCDMA/WIFI/Bluetooth communication

　　Cloud navigation, cloud driving recorder, cloud safety warning system functions

　　Front and rear driving recorder, rear view function

　　SOS emergency function

　　More than 800,000 data DSA systems, real-time cloud updates

　　Bluetooth hands-free calling function

　　G-Sensor Collision Save Lock

　　WeChat parking monitoring, real-time online monitoring of your car, can record and take photos

　　WeChat pick-up, convenient and fast

　　Voice control, free your hands

　　Location track can be checked at any time via WeChat

　　【Solution Features】

　　ARM Cortex A7 quad-core processor, clocked at up to 1.4GHz

　　Memory: 1GB DDR3; 8GB NAND/EmmC 4.5

　　High-speed OTG USB2.0

　　Support GSM/GPRS/EDGE/WCDMA/HSDPA/HSUPA baseband

　　5MP front camera; 1MP rear view camera

　　Integrated WIFI/BT/GPS/FM

　　3. Toshiba Smart Rearview Mirror Solution

　　In recent years, driving safety has received more and more attention from the Chinese people. Toshiba also provides ICs and integrated circuits for driving safety assistance systems in this regard.

　　【Solution diagram】

　　TMPV7502XBG, with its excellent image processing effect, can provide detection and identification functions for pedestrians or moving objects on the road. In addition, its low power consumption and small package make it very suitable for applications in smart rearview mirrors and smart reflectors.