1. A semiconductor device comprising:
a membrane; and
a support section for supporting a peripheral edge portion of the membrane,
the membrane formed with a plurality of openings having longitudinal portions.
2. The semiconductor device according to claim 1, wherein
the membrane is formed with a rectangular opening elongated in one direction and another rectangular opening elongated in another direction perpendicular to the one direction alternately in the one direction and the other direction.
3. The semiconductor device according to claim 1, further comprising:
a plurality of piezoresistors formed on the membrane; and
a weight section formed on a same side as the support section with respect to the membrane and integrally held on a central portion of the membrane.
4. The semiconductor device according to claim 1, wherein
the support section is in the form of a quadrangular annulus in plan view, whose sectional area taken along a plane parallel to the surface connected to the membrane monotonically increases as separating from the membrane.
5. The semiconductor device according to claim 3, wherein
the weight section is in the form of an isosceles trapezoid in section widening as separating from the membrane.
6. The semiconductor device according to claim 3, wherein
the support section and the weight section are separated from each other by a groove section having a quadrangular annular shape in plan view.
7. The semiconductor device according to claim 6, wherein
the groove section has a section in the form of an isosceles trapezoid narrowing upward as separating from the membrane.
8. The semiconductor device according to claim 1, wherein
the membrane is made of SiO2.
9. The semiconductor device according to claim 1, wherein
the support section is made of Si.
10. The semiconductor device according to claim 3, wherein
the weight section is made of Si.
11. The semiconductor device according to claim 1, wherein
a thickness of the membrane is 1 to 10 \u03bcm.
12. A semiconductor device comprising:
a membrane; and
a support section for supporting a peripheral edge portion of the membrane,
the membrane formed with a plurality of b-shaped openings.
13. The semiconductor device according to claim 12, further comprising:
a plurality of piezoresistors formed on the membrane; and
a weight section formed on a same side as the support section with respect to the membrane and integrally held on a central portion of the membrane.
14. The semiconductor device according to claim 12, wherein
the support section is in the form of a quadrangular annulus in plan view, whose sectional area taken along a plane parallel to the surface connected to the membrane monotonically increases as separating from the membrane.
15. The semiconductor device according to claim 13, wherein
the weight section is in the form of an isosceles trapezoid in section widening as separating from the membrane.
16. The semiconductor device according to claim 13, wherein
the support section and the weight section are separated from each other by a groove section having a quadrangular annular shape in plan view.
17. The semiconductor device according to claim 16, wherein
the groove section has a section in the form of an isosceles trapezoid narrowing upward as separating from the membrane.
18. The semiconductor device according to claim 12, wherein
the membrane is made of SiO2.
19. The semiconductor device according to claim 12, wherein
the support section is made of Si.
20. The semiconductor device according to claim 13, wherein
the weight section is made of Si.
21. The semiconductor device according to claim 12, wherein
a thickness of the membrane is 1 to 10 \u03bcm.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A fluorescent lamp ballast control circuit comprising:
a ballast controller IC for driving a fluorescent lamp in a half-bridge topology, the ballast controller IC having a dim control input; and
a control circuit receiving an input signal and providing an output signal to the ballast controller IC dim control input, the control circuit further receiving a feedback signal indicative of a fluorescent lamp current, wherein the control circuit output signal is based on the control circuit input signal and the feedback signal to set and keep the lamp current at a desired setting based on the control circuit input signal;
wherein the control circuit output signal is based in part on a feed forward of the control circuit input signal and based in part on an error determined by comparing the control circuit input signal to the feedback signal.
2. A fluorescent lamp ballast control circuit comprising:
a ballast controller IC for driving a fluorescent lamp in a half-bridge topology; and
a control circuit receiving an input signal and providing an output signal to the ballast controller IC, the control circuit further receiving a feedback signal indicative of a fluorescent lamp current, wherein the control circuit output signal is based on the input signal and the feedback signal;
wherein the control circuit output signal is based in part on a feed forward of the input signal and based in part on an error determined by comparing the input signal to the feedback signal;
wherein the output signal is based on a weighted sum of the feed forward and the error.
3. The fluorescent lamp ballast control circuit of claim 2 wherein the weighted sum is composed of a greater weighting of the feed forward and a lesser weighting of the error.
4. The fluorescent lamp ballast control circuit of claim 3 wherein the output signal is about 80% based on the feed forward and is about 20% based on the error.
5. In combination with a fluorescent lamp ballast, the improvement comprising:
a ballast control circuit including a ballast controller IC for driving a fluorescent lamp in a half-bridge topology, the ballast controller IC having a dim control input and a control circuit receiving an input signal and providing an output signal to the ballast controller IC dim control input, the control circuit further receiving a feedback signal indicative of a fluorescent lamp current, wherein the control circuit output signal is based on the control circuit input signal and the feedback signal to set and keep the lamp current at a desired setting based on the control circuit input signal;
wherein the control circuit output signal is based in part on a feed forward of the control circuit input signal and based in part on an error determined by comparing the control circuit input signal to the feedback signal.
6. In combination with a fluorescent lamp ballast, the improvement comprising:
a ballast control circuit including a ballast controller IC for driving a fluorescent lamp in a half-bridge topology, and a control circuit receiving an input signal and providing an output signal to the ballast controller IC, the control circuit further receiving a feedback signal indicative of a fluorescent lamp current, wherein the control circuit output signal is based on the input signal and the feedback signal;
wherein the control circuit output signal is based in part on a feed forward of the input signal and based in part on an error determined by comparing the input signal to the feedback signal;
wherein the output signal is based on a weighted sum of the feed forward and the error.
7. The combination of claim 6 wherein the weighted sum is composed of a greater weighting of the feed forward and a lesser weighting of the error.
8. The combination of claim 7 wherein the output signal is about 80% based on the feed forward and is about 20% based on the error.