CCD with improved substrate voltage setting circuit
View Patent ↗An image sensor includes a plurality of pixels for converting incident photons into electrical charge; an overflow drain to draw off excess charge from at one or more of the pixels; a mechanism for summing charge from two or more of the pixels; a first network of resistive devices generating a first overflow drain voltage where at least one of the resistive devices has, in parallel, a fuse that can be opened in response to an external stimulus to provide the optimum overflow drain voltage for pixel anti-blooming protection and saturation signal level for when a plurality of pixels are summed together; and a second network of resistive devices connected to the first network of resistive devices generating a second overflow drain voltage where the second overflow drain voltage is a fraction of the first overflow drain voltage and the second overflow drain voltage provides the optimum overflow drain voltage for pixel anti-blooming and saturation signal level for when none or substantially none of the plurality of pixels are summed together.
1. An image sensor comprising:
(a) a plurality of pixels for converting incident photons into electrical charge;
(b) an overflow drain to draw off excess charge from at least one or more of the pixels;
(c) a mechanism for summing charge from two or more of the pixels;
(d) a first network of resistive devices generating a first overflow drain voltage where at least one of the resistive devices has, in parallel, a fuse that can be opened in response to an external stimulus to provide the optimum overflow drain voltage for pixel anti-blooming protection and saturation signal level for when a plurality of pixels are summed together; and
(e) a second network of resistive devices connected to the first network of resistive devices generating a second overflow drain voltage where the second overflow drain voltage is a fraction of the first overflow drain voltage and the second overflow drain voltage provides the optimum overflow drain voltage for pixel anti-blooming and saturation signal level for when none or substantially none of the plurality of pixels are summed together.
2. The image sensor of claim 1 , further comprising a plurality of additional networks of resistive devices.
3. The image sensor of claim 1 , wherein at least one of the resistive devices is a resistor.
4. The image sensor of claim 1 , wherein at least one of the resistive devices is a field effect transistor.
5. The image sensor of claim 1 , wherein at least one of the fuses is replaced by an anti-fuse.
6. The image sensor of claim 1 , wherein the plurality of pixels form a charge coupled device.
7. The image sensor of claim 1 , wherein the plurality of pixels are each connected directly to the gate of a field effect transistor or indirectly connected to the gate of a field effect transistor through a transfer gate and floating diffusion.
8. The image sensor of claim 1 , wherein the number of plurality of pixels summed together is 2.
9. The image sensor of claim 1 , wherein the number of plurality of pixels summed together is 3.
10. The image sensor of claim 1 , wherein the number of plurality of pixels summed together is 4.
11. The image sensor of claim 2 , wherein at least one of the resistive devices is a resistor.
12. The image sensor of claim 2 , wherein at least one of the resistive devices is a field effect transistor.
13. The image sensor of claim 2 , wherein at least one of the fuses is replaced by an anti-fuse.
14. The image sensor of claim 2 , wherein the plurality of pixels form a charge coupled device.
15. The image sensor of claim 2 , wherein the plurality of pixels are each connected directly to the gate of a field effect transistor or indirectly connected to the gate of a field effect transistor through a transfer gate and floating diffusion.
16. The image sensor of claim 2 , wherein the number of plurality of pixels summed together is 2.
17. The image sensor of claim 2 , wherein the number of plurality of pixels summed together is 3.
18. The image sensor of claim 2 , wherein the number of plurality of pixels summed together is 4.
19. A camera comprising:
an image sensor comprising:
(a) a plurality of pixels for converting incident photons into electrical charge;
(b) an overflow drain to draw off excess charge from at one or more of the pixels;
(c) a mechanism for summing charge from two or more of the pixels;
(d) a first network of resistive devices generating a first overflow drain voltage where at least one of the resistive devices has, in parallel, a fuse that can be opened in response to an external stimulus to provide the optimum overflow drain voltage for pixel anti-blooming protection and saturation signal level for when a plurality of pixels are summed together; and
(e) a second network of resistive devices connected to the first network of resistive devices generating a second overflow drain voltage where the second overflow drain voltage is a fraction of the first overflow drain voltage and the second overflow drain voltage provides the optimum overflow drain voltage for pixel anti-blooming and saturation signal level for when none or substantially none of the plurality of pixels are summed together.
20. The camera of claim 19 further comprising a plurality of additional networks of resistive devices.
21. The camera of claim 19 , wherein at least one of the resistive devices is a resistor.
22. The camera of claim 19 , wherein at least one of the resistive devices is a field effect transistor.
23. The camera of claim 19 , wherein at least one of the fuses is replaced by an anti-fuse.
24. The camera of claim 19 , wherein the plurality of pixels form a charge coupled device.
25. The camera of claim 19 , wherein the plurality of pixels are each connected directly to the gate of a field effect transistor or indirectly connected to the gate of a field effect transistor through a transfer gate and floating diffusion.
26. The camera of claim 19 , wherein the number of plurality of pixels summed together is 2.
27. The camera of claim 19 , wherein the number of plurality of pixels summed together is 3.
28. The camera of claim 19 , wherein the number of plurality of pixels summed together is 4.
29. The image sensor of claim 20 , wherein at least one of the resistive devices is a resistor.
30. The image sensor of claim 20 , wherein at least one of the resistive devices is a field effect transistor.
31. The image sensor of claim 20 , wherein at least one of the fuses is replaced by an anti-fuse.
32. The image sensor of claim 20 , wherein the plurality of pixels form a charge coupled device.
33. The image sensor of claim 20 , wherein the plurality of pixels are each connected directly to the gate of a field effect transistor or indirectly connected to the gate of a field effect transistor through a transfer gate and floating diffusion.
34. The image sensor of claim 20 , wherein the number of plurality of pixels summed together is 2.
35. The image sensor of claim 20 , wherein the number of plurality of pixels summed together is 3.
36. The image sensor of claim 20 , wherein the number of plurality of pixels summed together is 4.