InventorsAssigneeUS Classes330/260, Having signal feedback means330/303, Including an active device in the filter means340/572.1, Detectable device on protected article (e.g., "tag")340/10.1Interrogation responseAttorney, Agent or FirmInternational ClassesH03F 3/45H04Q 5/22 H03F 3/191 G08B 13/14 Issued Patent Number:7385448Abstract texta circuit for an RFID device in one embodiment includes an operational amplifier having a first input, a second input, and an output where the first input receives an incoming signal, arid the second input is coupled to the output via a feedback loop. An operational amplifier for an RFID device according to another embodiment compares an output of the operational amplifier to an incoming baseband signal, A circuit according to another embodiment includes an operational amplifier having a first input, a second input, and an output, wherein the first input receives an incoming signal, and wherein the second input is coupled to the output via a feedback loop. A comparator having one input is coupled to the output of the operational amplifier, another input receiving the incoming signal, and an output for outputting an outgoing signal. Methods for adjusting a filtering characteristic of an operational amplifier are also disclosed. |
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