Switched-capacitor structures with enhanced isolation
First Claim
Patent Images
1. A switched-capacitor stage that operates in a sample mode and a transfer mode, the stage comprising:
- first and second sample switches;
a buffer transistor having a control terminal coupled to said first sample switch and also having a current terminal;
a sample capacitor coupled between said current terminal and second sample switch to thereby receive a sample charge Qs when said first and second sample switches are closed in said sample mode; and
first and second transfer switches that are respectively coupled to said control and said current terminals to bias off said buffer transistor and transfer at least a portion of said sample charge Qs to said transfer capacitor when said first and second transfer switches are closed in said transfer mode.
0 Assignments
0 Petitions
Accused Products
Abstract
Switched-capacitor structures are provided that reduce distortion and noise in their processed signals because they increase isolation between structural elements and ensure that selected elements are securely turned off in one mode and quickly turned on in another mode.
-
Citations
8 Claims
-
1. A switched-capacitor stage that operates in a sample mode and a transfer mode, the stage comprising:
-
first and second sample switches;
a buffer transistor having a control terminal coupled to said first sample switch and also having a current terminal;
a sample capacitor coupled between said current terminal and second sample switch to thereby receive a sample charge Qs when said first and second sample switches are closed in said sample mode; and
first and second transfer switches that are respectively coupled to said control and said current terminals to bias off said buffer transistor and transfer at least a portion of said sample charge Qs to said transfer capacitor when said first and second transfer switches are closed in said transfer mode. - View Dependent Claims (2, 3, 4)
-
-
5. A pipelined analog-to-digital converter that converts an analog signal to a corresponding digital signal, comprising:
-
a sampler that provides a sample signal in response to said analog signal;
an initial converter stage that processes said sample signal to provide a residue signal and respective bits of said digitalsignal; and
at least one successive converter stage that processes a preceding residue signal to provide a successive residue signal and respective bits of said digital signal wherein a final converter stage only provides said respective bits;
and wherein said sampler operates in a sample mode and a transfer mode and includes;
a) first and second sample switches;
b) a buffer transistor having a control terminal coupled to said first sample switch and also having a current terminal;
c) a sample capacitor coupled between said current terminal and second sample switch to thereby receive a sample charge Qs when said first and second sample switches are closed in said sample mode; and
d) first and second transfer switches that are respectively coupled to said control and said current terminals to bias off said buffer transistor and transfer at least a portion of said sample charge Qs to said transfer capacitor when said first and second transfer switches are closed in said transfer mode. - View Dependent Claims (6, 7, 8)
-
Specification