Abstract: A multi-channel Class D audio amplifier is provided to substantially reduce channel-to-channel crosstalk by employing in each channel a local triangle ramp generator controlled by a single global digital timing signal. The noise critical timing/integrating capacitor for the triangle ramp generator resides locally in each channel and adjacent to the PWM comparator of that channel and referenced to the local ground of that channel. The amplifier can also include a duty cycle limitation circuit to limit output power availability depending on the impedance of any attached loads (speakers).

Abstract: A multi-channel Class D audio amplifier is provided to substantially reduce channel-to-channel crosstalk by employing in each channel a local triangle ramp generator controlled by a single global digital timing signal. The noise critical timing/integrating capacitor for the triangle ramp generator resides locally in each channel and adjacent to the PWM comparator of that channel and referenced to the local ground of that channel. The amplifier can also include a duty cycle limitation circuit to limit output power availability depending on the impedance of any attached loads (speakers).

Abstract: A multi-channel Class D audio amplifier is provided to substantially reduce channel-to-channel crosstalk by employing in each channel a local triangle ramp generator controlled by a single global digital timing signal. The noise critical timing/integrating capacitor for the triangle ramp generator resides locally in each channel and adjacent to the PWM comparator of that channel and referenced to the local ground of that channel. The amplifier can also include a duty cycle limitation circuit to limit output power availability depending on the impedance of any attached loads (speakers).

Abstract: A multi-channel Class D audio amplifier is provided to substantially reduce channel-to-channel crosstalk by employing in each channel a local triangle ramp generator controlled by a single global digital timing signal. The noise critical timing/integrating capacitor for the triangle ramp generator resides locally in each channel and adjacent to the PWM comparator of that channel and referenced to the local ground of that channel. The amplifier can also include a duty cycle limitation circuit to limit output power availability depending on the impedance of any attached loads (speakers).

Abstract: Described herein are several configurations of Class-D audio amplifiers, including a single-ended and a bridge-tied load (BTL) configuration, in which voltage-mode control and average current-mode control circuitry in feedback loops can be included to control the outputs of the Class-D amplifier to reduce open-loop errors and maintain a relatively high loop gain over an expected audio frequency range. The average current-mode control circuitry monitors current through a resistor common to both a current flow into a positive terminal of a loudspeaker associated with the amplifier and a current flow into a negative terminal of the loudspeaker. The voltage-mode control circuitry works with the average current-mode control circuitry in controlling the output of the Class-D audio amplifier.

Abstract: A multi-channel Class D audio amplifier is provided to substantially reduce channel-to-channel crosstalk by employing in each channel a local triangle ramp generator controlled by a single global digital timing signal. The noise critical timing/integrating capacitor for the triangle ramp generator resides locally in each channel and adjacent to the PWM comparator of that channel and referenced to the local ground of that channel. The amplifier can also include a duty cycle limitation circuit to limit output power availability depending on the impedance of any attached loads (speakers).

Abstract: A multi-channel Class D audio amplifier is provided to substantially reduce channel-to-channel crosstalk by employing in each channel a local triangle ramp generator controlled by a single global digital timing signal. The noise critical timing/integrating capacitor for the triangle ramp generator resides locally in each channel and adjacent to the PWM comparator of that channel and referenced to the local ground of that channel. The amplifier can also include a duty cycle limitation circuit to limit output power availability depending on the impedance of any attached loads (speakers).

Abstract: An audio amplifier is powered by a switch mode power supply optimized for audio applications. The power supply includes a rectifier circuit and a discontinuous mode multiphase isolated flyback power circuit and does not require a separate power factor correction stage. The discontinuous mode multiphase isolated flyback power circuit includes multiple isolated flyback converters operating synchronously to each convert a portion of the power and supply a phase-summed direct current voltage to the audio amplifier.

Abstract: An audio amplifier is powered by a switch mode power supply optimized for audio applications. The power supply includes a rectifier circuit and a discontinuous mode multiphase isolated flyback power circuit and does not require a separate power factor correction stage. The discontinuous mode multiphase isolated flyback power circuit includes multiple isolated flyback converters operating synchronously to each convert a portion of the power and supply a phase-summed direct current voltage to the audio amplifier.

Abstract: An audio amplifier is powered by a switch mode power supply optimized for audio applications. The power supply includes a rectifier circuit and a discontinuous mode multiphase isolated flyback power circuit and does not require a separate power factor correction stage. The discontinuous mode multiphase isolated flyback power circuit includes multiple isolated flyback converters operating synchronously to each convert a portion of the power and supply a phase-summed direct current voltage to the audio amplifier.

Abstract: An audio amplifier is powered by a switch mode power supply optimized for audio applications. The power supply includes a rectifier circuit and a discontinuous mode multiphase isolated flyback power circuit and does not require a separate power factor correction stage. The discontinuous mode multiphase isolated flyback power circuit includes multiple isolated flyback converters operating synchronously to each convert a portion of the power and supply a phase-summed direct current voltage to the audio amplifier.

Abstract: An air bag guide (44) for a vehicle seat component (14) includes flexible inner and outer panels (46, 48) having outer extremities (50, 54) located adjacent a release seam (32) of a trim cover (30), with the outer extremity (50) of the flexible inner panel secured to the trim cover, and with the outer extremity (54) of the flexible outer panel (48) unconnected to the trim cover and curved to provide a guide flap (62).

Abstract: An air bag guide (44) for a vehicle seat component (14) includes flexible inner and outer panels (46, 48) having outer extremities (50, 54) located adjacent a release seam (32) of a trim cover (30), with the outer extremity (50) of the flexible inner panel secured to the trim cover, and with the outer extremity (54) of the flexible outer panel (48) unconnected to the trim cover and curved to provide a guide flap (62).

Abstract: A tuned vibration absorbing system (12) for a seat system (10) includes a flexible extension member (32) that is coupled to the seat system (10). A suspended element (34) is coupled to the flexible extension member (32). The flexible extension member (32) and the suspended element (34) are configured to absorb vibration within the seat system (10). A method of designing and manufacturing a seat system (10) includes designing the tuned vibration absorbing system (12) with the flexible extension member (32) and the suspended element (34) to absorb vibration within the seat system (10), which is then manufactured and coupled to the seat system (10).

Abstract: A tuned vibration absorbing system (12) for a seat system (10) includes a flexible extension member (32) that is coupled to the seat system (10). A suspended element (34) is coupled to the flexible extension member (32). The flexible extension member (32) and the suspended element (34) are configured to absorb vibration within the seat system (10). A method of designing and manufacturing a seat system (10) includes designing the tuned vibration absorbing system (12) with the flexible extension member (32) and the suspended element (34) to absorb vibration within the seat system (10), which is then manufactured and coupled to the seat system (10).

Abstract: A seat (22) for mounting in a vehicle generally includes an entire video recording system (20). The video recording system (20) has a camera (40) extending above the seat (22) and mounted, via a support (42), to a back frame (26) of the seat (22). The camera (40) is spaced from the headrest (29) and is preferably close to the longitudinal centerline of the vehicle. An audio receiver (48) and controller (80) are mounted in the seat back (28), while a recorder (68) and display unit (54) are mounted to the seat bottom (32). A power and communications wire bundle (82) is disposed to connect the recording system (20) to the vehicle's systems. The recording system (20) may include a mechanism for limiting access to the videotape and a mechanism for heating and cooling the recorder.