Patent ID: 8988084
Filing Date: 2015-03-24
Classification: B60R

Abstract:
1. A device for monitoring at least one energy reserve capacitor in a restraint system, comprising: a microcontroller configured to monitor a capacitance of the at least one energy reserve capacitor; a voltage converter configured to convert an input voltage to a higher output voltage and charge the at least one energy reserve capacitor using the higher output voltage; and a rectifier and a voltage divider configured to determine a charging current and a difference between at least one observed peak voltage value and at least one subsequently observed static voltage value, the at least one peak voltage value being a result of an active phase of the voltage converter and the at least one static voltage value being a result of an inactive phase of the voltage converter following the active phase of the voltage converter, a waiting period following the at least one observed peak voltage value, wherein the microcontroller generates a signal to selectively shut the voltage converter off to provide defined starting conditions, and wherein the voltage converter, the rectifier, and the voltage divider are configured to monitor an ohmic internal resistance of the at least one energy reserve capacitor.