Capacitive array
A capacitive array comprising at least two capacitive entities, comprising a substrate layer. The substrate layer comprises a comb comprising at least four substantially identical teeth, and, for each capacitive entity, a set of fingers comprising one or more interlinked fingers. At least two sets of fingers comprise a different number of fingers, each finger being nested between two teeth of the comb and being substantially identical to the other fingers. The fingers of each set of fingers are substantially distributed symmetrically relative to a median axis of the comb. The comb and the fingers are integrated in a single block.
1. A capacitive array having at least two capacitive entities, comprising:
a substrate layer comprising:
a comb including at least four substantially identical teeth; and
for each capacitive entity, a set of fingers with one or more interlinked fingers, at least two sets of fingers comprising a different number of fingers, each finger being nested between two teeth of the comb and being substantially identical to the other fingers, the fingers of each set of fingers being substantially distributed symmetrically relative to a median axis of the comb, wherein the comb and the fingers are integrated in a single block.
2. A capacitive array according to claim 1 , further comprising:
a set of connecting tracks above the substrate layer; and
a surface screen element between the substrate layer and the connecting tracks.
3. A capacitive array according to claim 1 , wherein each set of fingers is constructed from a basic element comprising a single finger.
4. A capacitive array according to claim 3 , further comprising:
a set of connecting tracks above the substrate layer; and
a surface screen element between the substrate layer and the connecting tracks.
5. A capacitive array according to claim 1 , wherein the value of each capacitive entity is chosen to be equal to the value of the lowest capacitive entity multiplied by an integer power of two.
6. A capacitive array according to claim 5 , further comprising:
a set of connecting tracks above the substrate layer; and
a surface screen element between the substrate layer and the connecting tracks.
7. A capacitive array according to claim 1 , further comprising a set of connecting tracks extending in the plane of the substrate layer.
8. A capacitive array according to claim 7 , further comprising:
an additional substrate layer below the substrate layer, comprising.
an additional comb substantially identical to the comb and for each finger, an additional finger nested in the teeth of the additional comb;
first link elements between the comb and the additional comb; and
second link elements between each finger and the corresponding additional finger.
9. A capacitive array according to claim 8 further comprising a lateral screen element between the additional substrate layer and the connecting tracks.
10. A capacitive array according to claim 1 , further comprising:
an additional substrate layer below the substrate layer, comprising:
an additional comb substantially identical to the comb and for each finger, an additional finger nested in the teeth of the additional comb;
first link elements between the comb and the additional comb; and
second link elements between each finger and the corresponding additional finger.
11. A digital to analogue converter comprising a capacitive array including at least two capacitive entities, comprising:
a substrate layer comprising:
a comb including at least four substantially identical teeth; and
for each capacitive entity, a set of fingers with one or more interlinked fingers, at least two sets of fingers comprising a different number of fingers, each finger being nested between two teeth of the comb and being substantially identical to the other fingers, the fingers of each set of fingers being substantially distributed symmetrically relative to a median axis of the comb, wherein the comb and the fingers are integrated in a single block.
12. An analogue to digital converter comprising a digital-analogue converter according to claim 11 .
13. A capacitive array comprising:
a comb including a plurality of substantially identical teeth; and
a plurality of sets of fingers with one or more interlinked fingers, at least two sets of fingers comprising a different number of fingers, each finger being nested between two teeth of the comb and being substantially identical to the other fingers, the fingers of each set of fingers being substantially distributed symmetrically relative to a median axis of the comb, wherein the comb and the fingers are integrated in a single block.
14. A capacitive array according to claim 13 , further comprising:
a set of connecting tracks above a substrate layer including the capacitive array; and
a surface screen element between the substrate layer and the connecting tracks.
15. A capacitive array according to claim 13 , wherein each set of fingers is constructed from a basic element comprising a single finger.
16. A capacitive array according to claim 13 , wherein the capacitive array includes a capacitive entity having only a single finger, said finger being positioned substantially on the median axis.
17. A capacitive array according to claim 13 , further comprising a plurality of substrate layers.