公开(公告)号：US20250060767A1

公开(公告)日：2025-02-20

申请号：US18722051

申请日：2022-12-02

Applicant: Endress+Hauser Flowtec AG

Inventor： Pascal Buchschacher ,  Alex Huber ,  Hanspeter Schmid ,  Werner Tanner

IPC: G05F1/46 ,  H03K3/037

Abstract: The signal transmission system comprises a transmitter circuit, a receiver circuit and a signal cable. A current divider is formed by a terminating resistor between the signal conductors of the signal cable. The transmitter circuit drives a loop current. When the receiver circuit input voltage has a voltage level above a first switching voltage threshold value, the output voltage assumes a first voltage level. The output voltage maintains the first voltage level when the input voltage is below the first switching voltage threshold value but above a second switching voltage threshold value. The transmitter circuit is configured to modulate the loop current with at least two different non-zero magnitudes at successive times. The first magnitude is greater than a first switching current threshold value and the second magnitude is less than the first switching current threshold value and greater than a second switching current threshold value.