Infineon TLE4941-1C

This article describes the differential two-wire Hall effect sensor ICs TLE4941-1 and TLE4941-1C for wheel speed applications. In uncalibrated mode, an occasionally short initial offset settling time td,input may delay the detection of the input signal. The magnetic input signal is tracked by a speed ADC and monitored within the digital circuit; signal transients must exceed the threshold to be detected. During the period from magnetic input signal startup to reaching its second extremum, the PGA switches to the appropriate position and the digital noise constant value changes accordingly, resulting in a variation in phase shift between the magnetic input signal and the output signal. In calibrated mode, the output switches at the zero crossing of the input signal. TLE4941-1 differs from TLE4941 in that the first output edge may appear before the first zero crossing of the magnetic input signal, but the delay from signal startup to the first calibrated output signal is the same as that of TLE4941.

• In uncalibrated mode, initial offset settling time may delay input signal detection
• Magnetic input signal tracked and monitored by velocity ADC; signal transients must exceed threshold
• PGA switches position based on signal amplitude and initial offset value; digital noise constant changes accordingly
• In calibrated mode, output switches at input signal zero crossing
• First output edge may appear before first zero crossing of magnetic input signal

• Wheel speed applications