What is the standard voltage of LIN bus?
4 Answers
LIN bus operates at 12V. The master node is configured with a 1kΩ resistor terminating to 12V power supply, while slave nodes are configured with 30kΩ resistors terminating to 12V power supply. Below are relevant introductions about LIN bus: 1. Definition: LIN bus is a low-cost serial communication network defined for automotive distributed electronic systems, serving as a complement to other automotive multiplex networks like Controller Area Network (CAN). It's suitable for applications that don't require high bandwidth, performance, or fault tolerance. LIN bus is based on SCI (UART) data format, adopting a single-master/multi-slave mode, which is a special case of UART. 2. Objective: LIN aims to provide auxiliary functions for existing automotive networks (e.g. CAN bus), making it a supplementary bus network. In scenarios that don't require CAN bus's bandwidth and multifunctionality - such as communication between smart sensors and braking devices - using LIN bus can significantly reduce costs.
As an automotive electronics enthusiast, I've studied in-vehicle networks extensively. The LIN bus standard voltage is based on the vehicle's 12V DC system. During operation, the voltage varies between 0 and 12V: when dominant, it's close to the supply voltage (approximately 12V) representing logic low; when recessive, it's 0V representing logic high. The actual compatible range is relatively wide, functioning between 8 to 18V, but stable 12V is crucial. LIN is used for small components like lights or seat controls - voltage instability can cause malfunctions; common issues include battery aging or line interference causing fluctuations. It's recommended that vehicle owners regularly check battery health to avoid affecting safe driving.
I've driven quite a few cars and usually just remember some basic maintenance knowledge. The LIN bus voltage is typically around 12 volts. If the windows or sunroof get stuck, it might be due to voltage deviation – both too low or too high can cause trouble. The LIN bus handles some minor tasks, so if the voltage is unstable, you should check the battery or fuses. Don't rush to fix it yourself; it's safer to have a professional diagnose the issue to avoid damaging other components. Although such problems seem minor while driving, don't neglect regular maintenance.
With ten years of car repair experience, I've encountered common LIN bus faults. We tested the voltage to be normal around 12V, with clear logic signal transitions. If the multimeter shows below 10V or above 15V, the module will stop working. The causes are mostly poor grounding, blown fuses, or loose wiring. During repairs, first confirm if the voltage range of 8-18V is met. If the issue is simple, replace the fuse; otherwise, check the wiring. Car owners, don't attempt DIY fixes—leave it to the technicians for safety and reliability.
