Abstract: A sensor device (20) comprises a sensor package (22) having a cavity (24) formed therein, a sensor die (26) mounted on a bottom surface (28) of the cavity (24) and a protective coating (30) formed over the sensor die in the cavity. The protective coating (30) is formed from a material, preferably a polymer material, which is arranged to have a graduated cross-linking density such that the material at the top of the cavity (24) has a high density of cross-linking and the material at the bottom of the cavity (24), which material is in contact with the sensor die, has a low density of cross-linking.

Abstract: A control circuit (52) for controlling power supplied to an igniter element (54), includes a first input (70) for receiving an encoded input signal generated in response to the initiation of a firing mode and a diagnostic mode. The encoded input signal comprises a code portion (100) having at least two pulses, and a power portion (102). Logic circuitry (74) determines whether the code portion (100) is valid, the code portion (100) being determined valid when it meets predefined conditions within a predetermined time window, and provides an unlocking signal (Sfire) at an output (76) when the code portion (100) is determined to be valid. A switch (78), which has a control input coupled to the output (76) of the logic circuitry (74), is enabled on receipt of the unlocking signal so that power at the first input (70) of the control circuit (52) is supplied to the output of the switch for energizing the igniter element (54).

Abstract: A steering wheel shaft (103) position sensor includes a light emitter (110) fixed with respect to the shaft (103) and a pair of light detectors (111, 112) fixed with respect to the emitter (110). A disc (113) is mounted for rotation on the shaft (103) between the emitter (110) and the detectors (111, 112) and has a grey scale track extending circumferentially on the disc (113) between the emitter and one of the detectors (111), the grey scale varying from opaque to transparent to the light emitted by the emitter (110). A second, transparent track extends circumferentially on the disc (113) between the emitter and the other detector (112). The outputs of the two detectors (111, 112) are compared to provide an indication of the movement of the shaft (103).

Abstract: A rotation sensor (5) comprises a fixed member (10) and a rotatable member (20). The fixed member (10) contains a radiation emitter (40) which emits radiation along a path (35). The rotatable member (20) rotates about an axis (65) substantially perpendicular to the path (35) and has a head containing slots (25) arranged to periodically transmit and block the radiation emitted by the emitter (40). The fixed member (210) also has a radiation detector (50) which detects radiation transmitted by the slots (25) of the rotatable member (20). Thus, the rotational movement of the rotatable member (20) with respect to the fixed member (10) is sensed by the frequency of the radiation detected by the radiation detector (50).