Patent ID: 7948419

Claim:
A circuit configuration for obtaining a binary output signal, comprising: a magnetic-field sensor, which is supplied at two terminals with a supply voltage and which delivers from these terminals a current signal essentially alternating in pulse shape between two current values; a voltage-supply unit to supply the magnetic-field sensor with a stabilized supply voltage; a measuring device for tapping the pulse-shaped current signal from the magnetic-field sensor and for delivering a measuring signal; a signal-conditioning stage for forming an analogue voltage signal from the measuring signal; an analogue/digital converter stage for obtaining a digital voltage signal from the analogue voltage signal; a control stage for obtaining a first and a second signal value from the digital voltage signal, wherein the signal values represent the two current values of the current signal, alternating in pulse shape, as supplied by the magnetic-field sensor for supplying the currently obtained first and second signal values to a memory device after every pulse-shaped change in the current signal for identifying a digital changeover-threshold signal in accordance with a first algorithm from the real-time first and second signal values, the memory device storing the currently obtained first and second signal values; a digital/analogue converter stage for obtaining an analogue changeover-threshold signal from the digital changeover-threshold signal; and a comparator for comparing the analogue voltage signal with the analogue changeover-threshold signal and for creating the binary output signal in accordance this comparison.