Siemens Vdo Automotive Corporation

Siemens Aktiengesellschaft

Simon Makar

Stephan Bolz

Günter Lugert

Larry Hiltunen

Mary B McCoy

Rafael Cobas-Asensio

Jason Mucha

Changhong Zhang

A low-frequency PWM-modulated signal and a high-frequency, unmodulated signal for generating a high-frequency PWM-modulated signal is employed directly for driving an output stage of a device for noise suppression. The low-frequency signal and the high-frequency signal is advantageously provided by a microcontroller which already has an AD converter on the input side. The microcontroller furthermore already makes a PWM output signal with a high bit width available which has the high resolution necessary for driving the loudspeaker.

Drive circuit, device, and method for suppressing noise, and use

A fuel injector system () calculates a first derivative filtered signal and a second derivative filtered signal from an unpowered spool valve coil signal. When the spool valve () reaches the end of travel, either open or closed position, a flat slope f is generated on the falling edge of the bell shaped signal. The second derivative provides a readily apparent determination of when the steep slope occurs. A comparator () thereby need only determine when the second derivative is zero to identify that the spool valve has reached the end of travel.

End of valve motion detection for a spool control valve

Growing community of inventors

Macomb, MI, United States of America

Simon Makar