US6661283B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wide gain range and fine gain step programmable gain amplifier with single stage switched capacitor circuit
Assignee: National Semiconductor Corp
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Filing: 2002-10-03
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Granted: 2003-12-09
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Expires: 2022-10-03
Abstract
Abstract The present invention is directed towards a single stage switched capacitor programmable gain amplifier. The operation of the amplifier is described by a transfer function having two gain factors: (C 1 /C 2 ) and (C 2 /C 3 ). The transfer function is equal to the product of the two gain factors: (C 1 /C 2 )×(C 2 /C 3 ) such that the transfer function is equal to (C 1 /C 3 ). The combination of the two different gain factors provides a wider range and finer step programmability of the amplifier. The amplifier does not have an idle phase, which reduces power dissipation. Additionally, the amplifier requires less switching which results in reducing the thermal noise and the switching noise produced by the amplifier.
Inventors
- 👤 Bumha Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:25
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/45475; G; G11; G11C; G11C27/00; G11C27/02; G11C27/024; G11C27/026; H03F3/005; H03G; H03G1/00; H03G1/0005; H03G1/0088; H03G1/0094; H04; H04N; H04N25/00; H04N25/70; H04N25/76; H04N25/78; H03F2203/00; H03F2203/45; H03F2203/45514
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
147 words
A switched capacitor programmable amplifier circuit, comprising: a first capacitor that is configured to store a sampled charge that is associated with an input signal during a sampling phase and transfer the sampled charge during a holding phase; a second capacitor that is configured to discharge during the sampling phase and provide a first capacitive feedback path such that a first amplified charge is stored on the second capacitor during the holding phase; a third capacitor that is configured to provide a second capacitive feedback path during the sampling phase and discharge during the holding phase; and an amplifier that is configured to amplify the transferred sampled charge using the first capacitive feedback path to produce the first amplified charge during the holding phase and amplify the stored first amplified charge using the second capacitive feedback path to produce a second amplified charge during the sampling phase.
Claim 2
Dependent Claim
147 words
A switched capacitor programmable amplifier circuit, comprising: a first capacitor that is configured to store a sampled charge that is associated with an input signal during a sampling phase and transfer the sampled charge during a holding phase; a second capacitor that is configured to discharge during the sampling phase and provide a first capacitive feedback path such that a first amplified charge is stored on the second capacitor during the holding phase; a third capacitor that is configured to provide a second capacitive feedback path during the sampling phase and discharge during the holding phase; and an amplifier that is configured to amplify the transferred sampled charge using the first capacitive feedback path to produce the first amplified charge during the holding phase and amplify the stored first amplified charge using the second capacitive feedback path to produce a second amplified charge during the sampling phase.
Claim 3
Dependent Claim
39 words
The circuit of claim 1 , wherein the amplifier is further configured to transfer the sampled charge according to a ratio that is determined by the capacitance of the first capacitor divided by the capacitance of the second capacitor.
Claim 4
Dependent Claim
41 words
The circuit of claim 1 , wherein the amplifier is further configured to amplify the stored first amplified charge according to a ratio that is determined by the capacitance of the second capacitor divided by the capacitance of the third capacitor.
Claim 5
Dependent Claim
40 words
The circuit of claim 1 , wherein the amplifier is further configured to amplify the transferred sampled charge according to a ratio that is determined by the capacitance of the first capacitor divided by the capacitance of the third capacitor.
Claim 6
Dependent Claim
21 words
The circuit of claim 1 , wherein the third capacitor is further configured to transfer charge to a switched capacitor circuit.
Claim 7
Dependent Claim
16 words
The circuit of claim 1 , wherein the first and the third capacitors are variable capacitors.
Claim 8
Dependent Claim
29 words
The circuit of claim 6 , wherein the gain factor is proportional to the value of the first capacitor and inversely proportional to the value of the third capacitor.
Claim 9
Dependent Claim
126 words
A circuit for amplifying a signal, comprising: means for storing a sampled charge that is associated with an input signal during a sampling phase on a first capacitor; means for transferring the sampled charge from the first capacitor during the holding phase; means for providing a first capacitive feedback path through which a first amplified charge is stored on a second capacitor during the holding phase; means for providing a second capacitive feedback path during the sampling phase; means for amplifying the transferred sampled charge using the first capacitive feedback path to produce the first amplified charge during the holding phase; and means for amplifying the stored first amplified charge using the second capacitive feedback path to produce a second amplified charge during the sampling phase.
Claim 10
Dependent Claim
126 words
A circuit for amplifying a signal, comprising: means for storing a sampled charge that is associated with an input signal during a sampling phase on a first capacitor; means for transferring the sampled charge from the first capacitor during the holding phase; means for providing a first capacitive feedback path through which a first amplified charge is stored on a second capacitor during the holding phase; means for providing a second capacitive feedback path during the sampling phase; means for amplifying the transferred sampled charge using the first capacitive feedback path to produce the first amplified charge during the holding phase; and means for amplifying the stored first amplified charge using the second capacitive feedback path to produce a second amplified charge during the sampling phase.
Claim 11
Dependent Claim
40 words
The circuit of claim 8 , wherein the means for transferring the sampled charge transfers the sampled charge according to a ratio that is determined by the capacitance of the first capacitor divided by the capacitance of the second capacitor.
Claim 12
Dependent Claim
44 words
The circuit of claim 8 , wherein the means for amplifying the stored first amplified charge amplifies the stored first amplified charge according to a ratio that is determined by the capacitance of the second capacitor divided by the capacitance of the third capacitor.
Claim 13
Dependent Claim
42 words
The circuit of claim 8 , wherein the means for amplifying the transferred sampled charge amplifies the transferred sampled charge according to a ratio that is determined by the capacitance of the first capacitor divided by the capacitance of the third capacitor.
Claim 14
Dependent Claim
19 words
The circuit of claim 8 , further comprising means for selecting the values of the first and third capacitors.
Claim 15
Independent Claim
114 words
A method for amplifying a signal, comprising: storing a sampled charge that is associated with an input signal during a sampling phase on a first capacitor; transferring the sampled charge from the first capacitor during the holding phase; providing a first capacitive feedback path through which a first amplified charge is stored on a second capacitor during the holding phase; providing a second capacitive feedback path during the sampling phase; amplifying the transferred sampled charge using the first capacitive feedback path to produce the first amplified charge during the holding phase; and amplifying the stored first amplified charge using the second capacitive feedback path to produce a second amplified charge during the sampling phase.
Claim 16
Independent Claim
114 words
A method for amplifying a signal, comprising: storing a sampled charge that is associated with an input signal during a sampling phase on a first capacitor; transferring the sampled charge from the first capacitor during the holding phase; providing a first capacitive feedback path through which a first amplified charge is stored on a second capacitor during the holding phase; providing a second capacitive feedback path during the sampling phase; amplifying the transferred sampled charge using the first capacitive feedback path to produce the first amplified charge during the holding phase; and amplifying the stored first amplified charge using the second capacitive feedback path to produce a second amplified charge during the sampling phase.
Claim 17
Dependent Claim
34 words
The method of claim 13 , wherein the sampled charge is transferred according to a ratio that is determined by the capacitance of the first capacitor divided by the capacitance of the second capacitor.
Claim 18
Dependent Claim
36 words
The method of claim 13 , wherein the stored first amplified charge is amplified according to a ratio that is determined by the capacitance of the second capacitor divided by the capacitance of the third capacitor.
Claim 19
Dependent Claim
35 words
The method of claim 13 , wherein the transferred sampled charge is amplified according to a ratio that is determined by the capacitance of the first capacitor divided by the capacitance of the third capacitor.
Claim 20
Dependent Claim
19 words
The method of claim 13 , further comprising transferring charge from the third capacitor to a switched capacitor circuit.
Claim 21
Dependent Claim
17 words
The method of claim 13 , further comprising selecting the values of the first and third capacitors.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-12-08 | 2007-06-09 | 2007-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-12-08 | 2011-06-09 | 2011-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-12-08 | 2015-06-09 | 2015-12-09 | $7700.00 | Window Closed / Lapsed |