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IBS: Intelligent battery sensor

The IBS is a mechatronic, intelligent battery sensor with its own microcontroller. The microcontroller is an element of the electronics module. The electronics module records the voltage, the current flow and the temperature of the battery. The following components are fitted in the electronics module:

The IBS continuously measures the following values on the battery:

For data transfer, the IBS is connected to the DME (Digital Engine Electronics) or DDE (Digital Diesel Electronics) via the BSD (bit-serial data interface).

Fig 1: Digital Engine Electronics - Circuit Diagram
G09895367Courtesy of BMW OF NORTH AMERICA, INC.
Item Explanation
1 Measurement of the battery voltage between the positive battery terminal and negative battery terminal
2 Temperature measurement of the battery (T)
3 Microcontroller (μC) in the intelligent battery sensor (IBS)
4 Digital Engine Electronics (DME) or Digital Diesel Electronics (DDE)
5 Current measurement (A) [indirect, via the proportionally voltage drop (V) at the precision resistor (shunt)]
6 Negative battery terminal
7 Positive battery terminal
BSD Bit-serial data interface (BSD) for transfer of the values to the DME or DDE