Abstract: An adaptive measurement system measures a transition rate associated with an output of a device. An input signal that is characteristic of the output of the device is received by an input signal-to-frequency converter, which changes state based upon a characteristic of the input signal. The input signal-to-frequency converter provides a second signal, which reflects the state changes of the input signal-to-frequency converter. The second signal is sampled over a sample period and an instance of average transition rate is determined. A control subsystem may use the instance of average transition rate for regulating the device.
Abstract: A method of screening defects includes steps of: (a) measuring a quiescent current at a first supply voltage for each of a plurality of devices; (b) measuring a quiescent current at a second supply voltage for each of the plurality of devices; (c) generating a plot of the quiescent current measured at the first supply voltage vs. the quiescent current measured at the second supply voltage for each of the plurality of devices; (d) determining a range of intrinsic variation of quiescent current in the plot; and (e) identifying any of the plurality of devices corresponding to a measurement plotted outside the range of intrinsic variation as defective.
Abstract: A method and a device for measuring the speed of a pulse-activated electric motor are described. According to this method, the motor is fully activated at time intervals to be determined for a defined measuring time by the circuit element provided for timing and, in this time, the frequency of the current ripples, which is proportional to the motor speed, is measured. A current-proportional voltage measuring device is located on the circuit element, on whose load side are located an amplifier, filters, and an evaluation circuit in the form of a comparator for determining the frequency of the current ripples flowing in a measured phase during which the motor is fully activated.
Type:
Application
Filed:
September 12, 2003
Publication date:
July 1, 2004
Inventors:
Marc Micke, Holger Sievert, Juergen Hachtel, Guenther Hertlein