Patent ID: 6731160
Filing Date: 2004-05-04
Classification: H03G,H03H

Abstract:
An apparatus for providing an adjustable bandwidth high pass filter, the apparatus comprising:a highpass filter having an input capacitor coupled in series between an input and a resistive ladder having a plurality of resistances coupled in series, the coupling between the input capacitor and a first resistor of the resistive ladder defining a first tap and successive couplings between successive resistances of the resistive ladder forming successive taps, a last resistance of the resistive ladder being coupled to a ground, the first tap and the successive taps forming a plurality of outputs, the plurality of outputs selectively providing gain for the adjustable bandwidth high pass filter; a plurality of bandwidth adjusting resistances, each bandwidth adjusting resistance having a first side coupled to the first tap; and a plurality of switches that provide coupling of a second side of each of the bandwidth adjusting resistances to the ground; wherein a ratio of a first voltage at the first tap to a second voltage at a successive tap of the successive taps remains substantially independent of the number of closed switches of the plurality of switches and thereby also independent of the number of bandwidth adjusting resistances of the plurality of bandwidth adjusting resistances switched into the adjustable bandwidth pass filter.