Electronic device

• US 5,734,318 A
• Filed: 07/29/1996
• Issued: 03/31/1998
• Est. Priority Date: 07/27/1995
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Nitschke, Werner, Weber, Werner, Maier, Hermann
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): Wu, Daniel J.
• Application Number:
  US08/681,732
• Time in Patent Office: 610 Days
• Field of Search: 340/436, 340/438, 180/282, 280/735, 307/10.1
• US Class Current: 340/438
• CPC Class Codes: B60R 21/0173 Diagnostic or recording means therefor
• CPC Class Codes: G01R 31/2829 Testing of circuits in sensor or actuator systems testing of apparatus for measuring electric or magnetic variables G01R35/00; testing of indicating or recording apparatus G01D; in airbag systems B60R21/0173; checking gas analysers G01N33/007; monitoring or fail-safe circuits for electromagnets H01F7/1844

Abstract

An electronic device includes an acceleration-sensitive sensor, an electronic circuit arrangement for analyzing the output signal from the sensor, an ignition output element, an ignition element, and a safety device for the vehicle'"'"'s occupants. To test the operating readiness of the ignition element, an oscillator circuit is also provided, which applies an output signal to the ignition element. The resulting voltage drop obtained across the ignition element is compared by means of a window comparator to threshold values.

Claims

1. An electronic device comprising:

at least one acceleration-sensitive sensor;

an electronic circuit arrangement for analyzing an output signal of the sensor;

an ignition output element coupled to the electronic circuit arrangement;

an ignition element including an ignition primer and a capacitor, the ignition primer and the capacitor being connected in series;

at least one safety device for at least one vehicle occupant, the safety device being triggered by the ignition element; and

an oscillator circuit, an output terminal of the oscillator circuit being coupled to the ignition element for supplying a test current to the ignition element.

2. The electronic device according to claim 1, wherein the oscillator circuit emits a sinusoidal output signal.

3. The electronic device according to claim 1, wherein the oscillator circuit emits a square output signal.

4. The electronic device according to claim 1, further comprising:

a rectifying and smoothing component coupled to the output terminal of the oscillator circuit, the component rectifying and smoothing an output signal of the oscillator circuit; and

a window comparator for receiving an output signal of the rectifying and smoothing component and for comparing the output signal of the component with first and second threshold values.

5. The electronic device according to claim 4, further comprising:

a signal device; and

an output element coupled to the window comparator and to the signal device for activating the signal device as a function of the comparisons made by the window comparator.

6. The electronic device according to claim 1, wherein a first capacitance of the capacitor is less than a second capacitance sufficient to activate the ignition element.