Charge transfer system and method
View Patent ↗A charge transfer system includes a current-based input device for generating an input current signal, a temporary energy storage device, and an amplification device. A switching device couples the temporary energy storage device to the current-based input device during a first portion of a time period and to the amplification device during a second portion of a time period. The input current signal charges the temporary energy storage device, during the first portion of the time period, to generate an input voltage signal. The amplification device receives the input voltage signal during the second portion of the time period.
1. A charge transfer system comprising:
a current-based input device for generating an input current signal;
a temporary energy storage device;
an amplification device; and
a switching device for (A) coupling the temporary energy storage device to the current-based input device during a first portion of a time period, and (B) uncoupling the temporary energy storage device from the current based input device and coupling the temporary input device to the amplification device during a second portion of a time period;
wherein the input current signal charges the temporary energy storage device, during the first portion of the time period, to generate an input voltage signal;
wherein the amplification device receives the input voltage signal during the second portion of the time period.
2. The system of claim 1 wherein the current-based input device is a photodiode.
3. The system of claim 2 wherein the photodiode is incorporated into a detector array of a computerized axial tomography scanner.
4. The system of claim 1 wherein the current-based input device is a high-capacitance input device.
5. The system of claim 4 wherein the high-capacitance input device has a capacitance in the range of 50–200 picofarads.
6. The system of claim 4 wherein the capacitance of the temporary energy storage device is less than the capacitance of the high-capacitance input device.
7. The system of claim 1 wherein the temporary energy storage device is a capacitor.
8. The system of claim 1 wherein the amplification device is a delta-sigma converter.
9. The system of claim 8 wherein the delta-sigma converter is incorporated into a computerized axial tomography scanner.
10. The system of claim 1 wherein the switching device is a solid-state switching device.
11. A charge transfer system comprising:
a current-based input device for generating an input current signal;
a temporary energy storage device;
a first amplification device;
a second amplification device; and
a switching device for coupling the temporary energy storage device to the current-based input device during a first portion of a time period and to the amplification devices during a second portion of a time period;
wherein the input current signal charges the temporary energy storage device, during the first portion of the time period, to generate an input voltage signal; and
wherein each amplification device receives the input voltage signal during the second portion of the time period.
12. The system of claim 11 further comprising one or more additional amplification devices.
13. The system of claim 11 wherein the current-based input device is a photodiode that is incorporated into a detector array of a computerized axial tomography scanner.
14. The system of claim 13 wherein the capacitance of the temporary energy storage device is less than the capacitance of the photodiode.
15. The system of claim 11 wherein the temporary energy storage device is a capacitor.
16. The system of claim 11 wherein the amplification devices are delta-sigma converters.
17. The system of claim 11 wherein the switching device is a solid-state switching device.
18. A method of reducing the gain-bandwidth product, in a computerized axial tomography scanner, comprising:
generating an input current signal with a current-based input device;
coupling the current-based input device to a temporary energy storage device;
charging the temporary energy storage device, during a first portion of a time period, with the input current signal to generate an input voltage signal;
uncoupling the current-based input device from the temporary storage device;
coupling the temporary energy storage device to an amplification device; and
receiving on the amplification device, during a second portion of the time period, the input voltage signal.
19. The method of claim 18 wherein the current-based input device is a photodiode.
20. The method of claim 19 wherein the photodiode is incorporated into a detector array of a computerized axial tomography scanner.
21. The method of claim 18 wherein the current-based input device is a high-capacitance input device.
22. The method of claim 21 wherein the high-capacitance input device has an capacitance in the range of 50–200 picofarads.
23. The method of claim 21 wherein the capacitance of the temporary energy storage device is less than the capacitance of the high-capacitance input device.
24. The method of claim 18 wherein the temporary energy storage device is a capacitor.
25. The method of claim 18 wherein the amplification device is a delta-sigma converter.
26. The method of claim 25 wherein the delta-sigma converter is incorporated into a computerized axial tomography scanner.
27. The method of claim 18 wherein the switching device is a solid-state switching device.