Device and method for determining the state of rotation of a camshaft of an engine

An assembly, comprising:

• a communication bus;
• and
• first and second current source sensors electrically coupled to one another in parallel via the communication bus,
• each one of said first and second current source sensors comprised of
• an output for connection with the communication bus,
• a sensing element electrically reactive to passage of a mobile target past the sensing element, and electronics adapted to generate, from signals received from the sensing element, an intermediate signal to the output as a current having, dependent upon the passage of the mobile target past the sensing element, one of a first low level and a first high level, and
• an embedded intelligence module that measures a current of a first signal at the output and, responsive to a current level of the current of the first signal, modifies any of the first low level and the first high level of the intermediate signal respectively into a second low level and into a second high level,
• the communication bus being adapted to pass the first signal constituting a sum of a first intermediate signal generated by the first current source sensor and of a second intermediate signal generated by the second current source sensor.

A method for determining a state of rotation of at least one rotary shaft of an internal combustion engine, comprising:

• a. a first step (e1) of activating first and second current source sensors;
• b. a second step (e2) of detecting passage of a tooth of a target by the first current source sensor, and generating as a first intermediate signal a square-wave pulse indicative of said passage of the tooth past the first current source sensor;
• c. a third step (e3) of measuring a first signal passing along a communication bus, the first signal being a sum of the first intermediate signal generated by the first current source sensor and a second intermediate signal generated by the second current source sensor, and determining from said first signal that the first current source sensor generates a first high level on the first intermediate signal and that a measure of the first signal value corresponds to a first critical value;
• and
• d. a fourth step (e4) of modifying a first low level of the first intermediate signal to a second low level, and also modifying the first high level of the first intermediate signal to a second high level.