Zhang Hanyu said that the vehicle of your choice, let others see what you look like, your experience, and your future. For automotive electronics industry engineers, the design of a super high security and reliability of automotive electronic protection program is also true. Today to talk about the car power bus protection program how to design, as much as possible to meet the needs of automotive electronic protection while improving the protection level.
Now, the car has become the most important means of transport in human life. The safety of natural is a hot topic for the present, most manufacturers of automotive electronic protective way or to the power bus, USB interface, CAN bus, USB2.0, reverse video, USB3.0 etc, to provide customers with satisfactory from the electronic automotive electronic equipment protection program, provide solutions for both innovative and cost-effective for your application. The following is a popular problem in electronic dance electronic protection car design of automobile power bus protection scheme, the application background and the protection scheme of the circuit and application of TVS from transient suppression diode, scheme of application and scheme to illustrate and pay attention to matters such as a detailed analysis.

First, the application background:
1 automotive ignition switch, relay contacts, AC generators, fuel injectors and other electromagnetic interference;
2 directly affect the electronic module inside the car;
3 automotive electronics must pass I OS7637-2 power line application standards.

Two, the protection scheme and tage device: Tage device:
Transient suppression diode (TVS)
TVS [SM5S18A] Vbr:20.0-22.1V; Ir:5mA; Vrwm:18.0V, Ipp:123.0A; Vc (V): 29.2 package: DO-218AB
TVS [SM5S36A] Vbr:40.0-44.2V; Ir:5mA; Vrwm:36.0V, Ipp:62.0A; Vc (V): 58.1 package: DO-218AB
TVS [SM8S18A] Vbr:20.0-22.1V; Ir:5mA; Vrwm:18.0V, Ipp:226..0A; Vc (V): 29.2 package: DO-218AB
TVS [SM8S36A] Vbr:40.0-44.2V; Ir:5mA; Vrwm:36.0V, Ipp:114.0A; Vc (V): 58.1 package: DO-218AB

Three, program application:
1 vehicle navigation
2 reversing system
3 display instrument panel

Four, scheme and the matters needing attention
1 this scheme uses TVS tube specially used in automotive electronics to protect the electronic module from stress over-voltage.
2 the program for automotive electronics DC12V/ 24V power bus overvoltage protection solutions.
Five kinds of test conditions 3 this scheme can be I OS-7637-2 standard.