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AssigneeKoninklijke Philips Electronics N.V.
InventorWillem Hendrik Groeneweg
Estimating the term…
Summarizing, the present invention provides an IVC (100), comprising an operational amplifier (110) with an inverting input (112) and an output (113), and a feedback resistor ladder network (120) coupled between the output (113) and the inverting input (112). The feedback resistor ladder network (120) comprises a main chain (121) composed of a plurality of substantially identical unit resistors (RU) connected in series, and a plurality of branches (124i), each branch (124i) coupling a node (Xi) in the main chain (121) to the inverting input (112) of the operational amplifier (110), each branch (124i) comprising a selectable feedback switch (123i). Further, some of the branches (124i) comprise a non-unit resistor (RNUi) coupled in series with the corresponding selectable feedback switch (123i). Further, the present invention provides a circuit comprising a FIRDAC (20) and a bias block (30) for providing at least one bias current for the FIRDAC (20). The bias block (30) comprises at least one bias resistor (RB). The FIRDAC (20) is associated with at least one IVC (25, 26), configured as described above, wherein the unit resistors (RU) of the at least one IVC (25, 26) are substantially identical to the bias resistor (RB) of the bias block (30).
Current to voltage converter (100) with controllable gain, comprising:
Current to voltage converter according to any of the previous claims, wherein the resistance values of the non-unit resistor means are less than the resistance value of the unit resistor means (RU).
Current to voltage converter according to any of the previous claims, wherein each branch (124) defines a feedback path from the output (113) of the amplifier (110) to the inverting input (112) of the amplifier (110), and wherein neighboring branches have a constant resistance ratio of, for instance, approximately {square root}2.
Current to voltage converter according to any of the previous claims, wherein the number of unit resistor means (RU) in that part of the main chain (121) between the output (113) of the amplifier (110) a 0 dB node (X6) is even, and preferably equals 6 or 8.
Current to voltage converter according to any of the previous claims, wherein the non-unit resistor means (RNU2) in at least one of the branches (1242) comprises a parallel connection of two unit resistor means.
Current to voltage converter according to any of the previous claims, wherein the feedback resistor ladder network (120) comprises:
Current to voltage converter according to any of the previous claims, further comprising a current input terminal (126) for receiving a current input signal (Iin), wherein said current input terminal (126), through corresponding selectable current switches (125), is coupled to that terminal of each selectable feedback switch (123) that is directed towards the corresponding node (X) in the main chain (121).
Signal processing circuit, comprising at least one bias circuit (30) and at least one current to voltage converter (25;
Dependencies are inferred from the claim text.