摘要 |
A digitizer for a barcode scanner includes an amplifier and a comparator. The amplifier receives a feedback signal and a differentiated return signal on a first port, and a reference voltage signal on a second port. Based on a difference between voltages on the first and second ports, the amplifier outputs an output signal, which is limited between a maximum voltage value and a minimum voltage value. The output signal is delayed in phase, and the phase-delayed signal is input to a first port of a comparator, while the undelayed output signal is input to a second port of the comparator. Based on a comparison of the voltages on the first and second ports of the comparator, the feedback signal having one of a first voltage value and a second voltage value is obtained.
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