Oscillators – Automatic frequency stabilization using a phase or frequency... – Particular error voltage control
Patent
1995-11-27
1997-01-14
Mis, David
Oscillators
Automatic frequency stabilization using a phase or frequency...
Particular error voltage control
331 8, 327553, 327558, 360 51, H03L 7093, H03K 513, H03H 1104, H03H 1112
Patent
active
055943900
ABSTRACT:
An active filter includes a capacitor and a resistor coupled in parallel to an input terminal; a first current conveyor coupled between the capacitor and an output terminal; a second current conveyor coupled between the resistor and the output terminal; and a second capacitor coupled between the output terminal and ground. Proportionality constants between input and output currents of the current conveyors can be adjusted to reduce capacitance in the active filter and reduce the area required to fabricate the active filter in an integrated circuit. The active filter can replace a conventional loop filter in a phase-locked loop of a data separator integrated circuit. In a phase-locked loop, the polarity of a charge pump can be reversed to compensate for current reversal by the current conveyors in the active filter.
REFERENCES:
patent: Re28452 (1975-06-01), Lance
patent: 3909735 (1975-09-01), Anderson et al.
patent: 4338527 (1982-06-01), Nagano
patent: 4387348 (1983-06-01), Fritze
patent: 4983930 (1991-01-01), Wadsworth
patent: 5012133 (1991-04-01), Hughes
patent: 5028822 (1991-07-01), Hughes
patent: 5055719 (1991-10-01), Hughes
patent: 5109169 (1992-04-01), Hughes
patent: 5121085 (1992-06-01), Brown
patent: 5124666 (1992-06-01), Liu et al.
patent: 5138278 (1992-08-01), Stessen
patent: 5206541 (1993-04-01), Boahen et al.
patent: 5384502 (1995-01-01), Volk
patent: 5410271 (1995-04-01), Arbel
patent: 5504459 (1996-04-01), Gersbach et al.
National Semiconductor Data Book, "Floppy Disk Data Separator Design Guide for the DP8473", National Semiconductor Application Note 505, Lutz et al, date unknown, pp. 5-28 to 5-57.
Millers David T.
Mis David
National Semiconductor Corporation
Winters Paul J.
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