Description
This interface IC is designed for remote automotive sensors, especially between a main ECU and remote (sensor) units. It contains two identical interfaces and the main task of each interface is to supply one remote unit and to receive digital information from the same remote unit. It is also possible to send data as PWM voltage pulses to the remote unit, for example to program the remote unit for its special application. This is done by one active wire: the interface supplies the external unit with a pre-regulated voltage, the external unit transmits the digital information back to the interface by current modulation. A continuous diagnosis of the IC is running in the background. The diagnosis results can be requested by a microcontroller using the SPI interface.

FEATUREs and Benefits
■ Two identical interface channels for remote sensor units
■ Two connection modes: connection to OUTx and RETx or connection to OUTx and GND pin
■ 16 bit Standard SPI for control and diagnosis via a microcontroller
■ Supply voltage for each remote unit with a supply current up to 45mA
■ Current limitation with an analog feed back loop for each channel
■ Receive data from the remote unit by current modulation with a transmission rate of 10kHz
■ Transmission of data to the remote unit via PWM voltage pulses
■ Data input/output can be directly connected to a microcontroller input/output (CMOS)
■ Low current consumption
■ All pins to the external interface are short-circuit and high-voltage protected
■ High immunity against cross coupling between the two channels
■ The current modulation provides high noise immunity for data transfer

APPLICATION
■ Remote automotive sensors (between ECU and sensors).