Circuit for detecting and suppressing pulse-shaped interferences

Abstract

The circuit arrangement for detecting pulse-shaped interferences in an electrical signal comprises an input (7), a high-pass filter (8) having a cut-off frequency lying between 40 Hz and 1000 Hz, one or two signal paths (25, 25') and an output (5). A signal path (25) comprises a peak detector (10), a device (11) for determining a running average value, of its input signal, a delay unit (12) and a comparator (15). The output of the peak detector (10) is coupled via the device (11) for determining a running average value to a first input (13) of the comparator and via the delay unit (12) to a second input (14) of the comparator. The comparator compares the delayed output signal of the peak detector with the output signal of the device for determining the running average value and supplies an output signal to its output (16) if the output signal of the peak detector is larger than a times the output signal of the device for determining the running average value, where it holds that a>1. With this circuit arrangement, a more satisfactory detection of pulse-shaped interferences is attained (FIG. 3). The circuit arrangement may be used, for example, as a detector circuit in an arrangement for detecting and suppressing pulse-shaped interferences. (FIG. 1).