Abstract: A vehicle network system employing a controller area network protocol includes a bus, a first electronic control unit, and a second electronic control unit. The first electronic control unit transmits, via the bus, at least one data frame including an identifier relating to data used for a calculation for obtaining a message authentication code indicating authenticity of transmission content. The second electronic control unit receives the at least one data frame transmitted vis the bus and verifies the message authentication code in accordance with the identifier included in the at least one data frame.

Abstract: An electronic control unit is connected to a network in an in-vehicle network system. The electronic control unit includes a first control circuit and a second control circuit. The first control circuit is connected to the network via the second control circuit. The second control circuit performs a first determination process on a frame to determine conformity of the frame with a first rule. Upon determining that the frame conforms to the first rule, the second control circuit transmits the frame to the first control circuit. The first control circuit performs a second determination process on the frame to determine conformity of the frame with a second rule. The second rule is different from the first rule.

Abstract: A semiconductor device includes a semiconductor pellet (1), and a package having a pellet mount portion (21) on which a semiconductor pellet (1) is mounted. The semiconductor pellet (1) is mounted on the pellet mount portion (21) of the package through a joint material (6). The area of the surface of the pellet mount portion (21) on which the semiconductor pellet (1) is mounted is set to be smaller than the area of the surface of the semiconductor pellet (1) which is mounted on the pellet mount portion (21), thereby preventing the climb-up of the joint material (6) along the side surface of the semiconductor pellet (1).

Abstract: A method of manufacturing a semiconductor device which includes providing an insulating substrate with a semiconductor chip mounted on a first face thereof. An insulating package member which is fixed on the first face of the substrate surrounds and houses the semiconductor chip. Various manufacturing steps are described, such as molding, grinding, and machining. In one step, ultrasonic waves are used to drive a grinding head. In another step, a rotating grinding wheel is used to mill out a groove. The method is designed to reduce warpage and improve the flatness of the substrate.

Abstract: A semiconductor device which includes an insulating substrate having a semiconductor chip mounted on a first face thereof, and an insulating first package member fixed on the first face with surrounding the semiconductor chip. An insulating second package member is fixed on a second face of the substrate, which is opposite to the first face. The chip is housed in a first cavity formed by the substrate and the first package member. The first cavity is sealed by a first sealing member fixed on an opening end of the first package member. The first and second package members are respectively fixed on both sides of the substrate, so that the package is substantially or nearly symmetrical in structure in relation to the substrate. Thus, stresses in the substrate due to expansion and contraction thereof are almost or substantially balanced with each other in a firing or burning process, and as a result, warpage of the substrate is difficult to be generated and flatness of the mounting face of can be improved.