AN602

www.DataSheet4U.com AN602 Vishay Siliconix Driver ICs for Automotive Diagnostic Communications Meet ISO 9141 Standards A series of compact, single-ended bus drivers for automotive diagnostic applications enables communication over the relatively long distances between testing equipment and automotive electronic control units, while protecting sensitive logic devices from the hazards of the automotive environment. The Si9241AEY and Si9243EY are the first narrow-body, small outline products on the market to meet the ISO 9141 standard for this application. Vishay Siliconix ISO 9141 Drivers Vishay Siliconix has produced two drivers to meet ISO 9141 configurations. Each driver is housed in a small-outline surface-mount package with on-board fault protection to protect the controller and tester from the automotive environment. Both drivers have short circuit and over-temperature protection and open load detection. The devices protect against voltage transients ( –3 V 3 [VBAT, K and L] v 45 V), which exceed ISO 9141 (–1 V to 40 V). The Drivers The Si9241AEY (Figure 2) is designed for the user that needs only K-Line communication. The ECU controls the K output through Transmit Pin (Tx) and Chip Select Bar (CS). The fault detection circuitry monitors Tx and K to determine open and shorted loads. If K is high when Tx is low, the K-Line is shorted. Conversely, if K is low when Tx is high, the K-Line is open. Over-temperature protection is always enabled, so a fault is determined whene...