Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: Apparatus, systems, and methods for detecting the presence of a metallic surgical instrument. A metal detector for detecting insertion of a metallic surgical device into a hollow tube may include a switch, resonant circuit and a controller. The resonant circuit has a capacitor and a coil mounted to the hollow tube. The controller turn on the switch for a preselected time to temporarily provide a current to the resonant circuit and analyzes a resulting decaying voltage waveform originating from the resonant circuit when the switch is turned off in order to determine the presence and longitudinal depth of the metallic surgical device in the hollow tube.

Abstract: An improved device for regenerating an infrared signal transmitted over the air for use in detecting a 3-dimensional position of an object. The regeneration device includes an infrared signal transmitter and detector that receives from the object a responsive infrared signal in response to the infrared signal transmitted by the transmitter. A low pass filter receives the responsive infrared signal from the detector and outputs a low-pass filtered signal. A comparator compares the output of the infrared signal detector and output of the low pass filter and generates an output representing a logic state based on the comparison.

Abstract: A common mode controller circuit (60) for maintaining a common mode voltage (Vcm) at a first node (52) and a second node (54) in a sample-and-hold circuit receiving a pair of AC coupled differential input signals (Vinp, Vinn) includes first and second resistors (R1/R2) and third and fourth resistors (R3/R4), each set of resistors connected in series between the first and second nodes, and a differential amplifier (A1) having an inverting input terminal coupled to a third node (62) between the first and second resistors, a non-inverting input terminal coupled to a reference voltage (Vref) and an output terminal coupled to a fourth node (64) between the third and fourth resistors. The common mode voltage is sampled at the third node and the differential amplifier provides a sourcing output current indicative of the difference between the sampled common mode voltage and the reference voltage to drive the fourth node.

Abstract: A method for cascading a first amplifier stage and a second amplifier stage includes coupling the output terminal of the first amplifier stage to the power supply reference point of the second amplifier stage, modulating the power supply reference point of the second amplifier stage using the output current of the first amplifier stage, and generating a final output voltage at the output terminal of the second amplifier stage having a first voltage value relative to the power supply reference point of the first amplifier stage. The first voltage value is the sum of the output voltage of the first amplifier stage relative to its own power supply reference point and the output voltage of the second amplifier stage relative to its own power supply reference point. In one embodiment, the power supply reference point is the ground reference of the power source in the amplifier stage.