PSI5 is an open standard for bidirectional digital sensor data communication in vehicles. Compared to analog options, this solution has advantages particularly with respect to robustness, reliability, and costs. The standard is applied, among other fields of use, for connecting distributed sensors for the control of airbag systems, chassis, and powertrain.
The E981.08 supports the entire range of topologies for synchronous operation as described by the PSI5 specification (PSI5-P, PSI5-U, and PSI5-D). It provides four independent channels through which up to three distributed sensors each can be connected to a microcontroller. Each channel supplies its sensors, connected via a low-cost two-wire line, with a controlled direct current voltage. The bidirectional communication between microcontroller and sensors also makes use of the two-wire line by means of current or voltage modulation. The available data rata from sensor to microcontroller comes to 125 kbit/s. It is thus considerably higher than in LIN networks yet below CAN network data rates, but at lower wiring expense.
In addition to the PSI5 component E981.08 with four channels, the two-channel E981.07 is also available. Other components featuring the universal, fast, and safe sensor bus system PSI5 are in the development and planning stages.
Samples and evaluation boards are available and can be requested online at www.elmos.de