초록 ▼

A wide bandwidth slope detector has a comparator with first and second time constant circuits coupled to first and second inputs thereof. Where one time constant is on the order of three times the other, the comparator will change state in response to the slopes of an input analog signal coupled to

A wide bandwidth slope detector has a comparator with first and second time constant circuits coupled to first and second inputs thereof. Where one time constant is on the order of three times the other, the comparator will change state in response to the slopes of an input analog signal coupled to the time constant circuit. Feedback can be provided by a fixed resistor or by a tracking circuit. A smoothing or clipping circuit can be used to pre-process the input analog signals to eliminate noise therefrom. A bar code reading system combines first and second clipping circuits to smooth the highs and lows of the input signal, coupled to a slope detector. The tracking circuit can be used to provide a symmetrical hysteresis characteristic.

대표청구항 ▼

An amplitude independent slope detector for producing a binary output signal corresponding to a binary information sequence carried by an analog signal having varying peak amplitudes bounded by first and second slopes, wherein at least some of the amplitudes are substantially constant between respec

An amplitude independent slope detector for producing a binary output signal corresponding to a binary information sequence carried by an analog signal having varying peak amplitudes bounded by first and second slopes, wherein at least some of the amplitudes are substantially constant between respective slopes, the detector comprising: an input node to which the analog signal can be coupled, and an output node; a first, passive circuit, coupled to said input node, for detecting first and second slopes; a second circuit, coupled to said first circuit and said output node and responsive only to said detected slopes, for producing first and second binary output values at said output node, wherein each said output value is initiated when a respective one of said slopes is detected and maintained at said value in the presence of a substantially constant amplitude until the other of said slopes is detected.