Wave transmission lines and networks – Attenuators
Reexamination Certificate
2010-03-08
2011-12-13
Jones, Stephen (Department: 2817)
Wave transmission lines and networks
Attenuators
C327S308000
Reexamination Certificate
active
08076995
ABSTRACT:
An integrated digitally controlled linear-in-decibels attenuator circuit in which one or more sets of selection switches establish a desired attenuation by selectively connecting the input signal electrode to one or more corresponding resistive ladder networks connected in series, thereby providing a substantially more constant signal attenuation value over a wider frequency bandwidth. With a single resistive ladder network, attenuation control is achieved using a thermometer switching code. With multiple resistive ladder networks, coarse and fine attenuation control can be achieved using thermometer and bubble switching codes, respectively.
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Jones Stephen
National Semiconductor Corporation
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