Device for analyzing an alternating voltage or current including a variable D.C. component

US6147486A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Thomas Koss · Reutlingen, DE
• Guenter Nasswetter · Gomaringen, DE

Key dates

• Filing date: Jul 28, 1998
• Grant date: Nov 14, 2000
• Expiry date: Jul 28, 2018

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02D41/0097
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

The analysis or evaluation circuit for analyzing an alternating voltage or current signal that includes a D.C. voltage or D.C. current component includes a window comparator having a circuit portion for comparing the alternating voltage or current signal to an upper threshold and a lower threshold and another circuit portion for adjusting the upper and lower threshold when one of the upper and the lower thresholds is reached by the alternating voltage or current signal. By means of a VCL output signal that switches when a threshold adjustment occurs, a frequency dependent signal may be produced that can be analyzed to obtain a rotational speed of a rotational body from which the input alternating voltage or current is derived.