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AssigneeAnalog Devices, Inc.
InventorsHans Juergen Tucholski, Anthony Lawrence O'Brien
Estimating the term…
“A compensating circuit for use in a switch circuit comprising scaled current steering switches, a switch circuit comprising the compensating circuit, and a method for minimising time-skew in switching scaled current steering switches” An eight bit current steering DAC comprising scaled current steering switches (ST0,SF0,ST(n−1),SF(n−1)) (where n=8) comprises a comprising plurality of compensating MOS switches (SCT0 and SCF0 to SCT(n−1) for minimising time-skew when switching selected ones of the current steering switches from one state to another. The compensating switches (SCT,SCF) are of type similar to the current steering switches (STi and SFi), and are sized so that the combined switching load presented to the corresponding driver circuit (Di) by the sum of the parasitic load capacitance of the current steering switch (STi or SFi) and the corresponding compensating switch (SCTi or SCFi) is substantially similar for each driver circuit (Di). Thereby, selected current steering switches (ST0 and SF0 to ST(n−1) and SF(n−1)) are simultaneously switched in response to simultaneously applied switching signals from the driver circuits (Di).
A compensating circuit for providing switching load compensation for a plurality of scaled current steering switches selectively operable from one state to another state in response to respective switching signals, the compensating circuit being provided for facilitating substantially simultaneous switching of selected ones of the switches from one of the states to the other state in response to simultaneously applied switching signals, and comprising a scaled load compensating circuit for providing scaled switching load compensation for at least some of the current steering switches so that the switching loads presented to driver circuits of the respective current steering switches for switching thereof are substantially similar, the scaled load compensating circuit comprising:
A switch circuit comprising:
A current steering digital to analogue converter comprising:
A method for minimising time-skew in the selective switching of a plurality of current steering switches from one state to another state in response to respective simultaneously applied switching signals, the method comprising the step of providing scaled load compensation for at least some of the current steering switches so that the switching loads presented to driver circuits of the respective current steering switches are substantially similar, for facilitating substantially simultaneous switching of selected ones of the current steering switches from one of the states to the other state in response to the simultaneously applied switching signals, the scaled load compensation being provided by respective load compensating elements for the current steering switches for which load compensation is to be provided, the values of the switching load compensation provided by the respective load compensating elements being such that when combined with the switching load of the corresponding current steering switch, the combined switching load presented to the corresponding driver circuit is substantially similar for each current steering switch and its corresponding load compensating element, so that the selected current steering switches are switched from one of the states to the other state substantially simultaneously in response to simultaneously applied switching signals.
Dependencies are inferred from the claim text.