US6288669B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switched capacitor programmable gain and attenuation amplifier circuit
Assignee: Individual
•
Filing: 1999-07-15
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Granted: 2001-09-11
•
Expires: 2019-07-15
Abstract
Abstract A digitally programmable switched capacitor gain and attenuation circuit that uses the same switched capacitor array for a multitude of different gain and/or attenuation settings with a single operational amplifier is disclosed. With the top plates of the capacitors connected to the operational amplifier input, the unique switching of the bottom plates of the capacitor array elements between three voltages—the circuit output, the circuit input, or a chosen reference voltage such as a power supply midpoint voltage or a ground voltage of the circuit, makes this circuit arrangement's component area smaller and the operational amplifier's design specification less demanding for applications such as a digital camera front end analog processor.
Inventors
- 👤 Daramana G. Gata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:29
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/06; H03M1/0617; H03M1/0675; H03M1/0678; H03M1/068; H03M1/0682; G; G06; G06G; G06G7/00; G06G7/12; G06G7/18; G06G7/184; G06G7/186; G06G7/1865; H03G; H03G1/00; H03G1/0005; H03G1/0088; H03G1/0094; H03M1/66; H03M1/74; H03M1/80; H03M1/802; H03M1/804
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
120 words
A programmable switched capacitor gain and attenuation circuit comprising: an operational amplifier; N capacitors, each of the N capacitors having a top plate coupled to a first input of the operational amplifier, wherein N is an integer greater than one; N switching networks, each of the N switching networks is coupled to a corresponding bottom plate of a corresponding one of the N capacitors, each of the N switching networks is operable to switch the corresponding bottom plate to any one of a first input node, a first output of the operational amplifier, and a common node; and M capacitors each having a top plate coupled to a second input of the operational amplifier, wherein M is equal to N.
Claim 2
Dependent Claim
120 words
A programmable switched capacitor gain and attenuation circuit comprising: an operational amplifier; N capacitors, each of the N capacitors having a top plate coupled to a first input of the operational amplifier, wherein N is an integer greater than one; N switching networks, each of the N switching networks is coupled to a corresponding bottom plate of a corresponding one of the N capacitors, each of the N switching networks is operable to switch the corresponding bottom plate to any one of a first input node, a first output of the operational amplifier, and a common node; and M capacitors each having a top plate coupled to a second input of the operational amplifier, wherein M is equal to N.
Claim 3
Dependent Claim
22 words
The circuit of claim 1 further comprising a switch coupled between the first input of the operational amplifier and the common node.
Claim 4
Dependent Claim
19 words
The circuit of claim 2 further comprising a second input of the operational amplifier coupled to the common node.
Claim 5
Dependent Claim
19 words
The circuit of claim 1 further comprising a second input of the operational amplifier coupled to the common node.
Claim 6
Dependent Claim
29 words
The circuit of claim 4 wherein the first input of the operational amplifier is a negative input and the second input of the operational amplifier is a positive input.
Claim 7
Dependent Claim
64 words
The circuit of claim 1 further comprising M switching networks, each of the M switching networks is coupled to a corresponding bottom plate of a corresponding one of the M capacitors, each of the M switching networks is operable to switch the corresponding bottom plate to any one of a second input node, a second output of the operational amplifier, and the common node.
Claim 8
Dependent Claim
24 words
The circuit of claim 6 further comprising a switch coupled between the common node and the first and second input of the operational amplifier.
Claim 9
Dependent Claim
51 words
The circuit of claim 6 wherein the first input of the operational amplifier is a negative input, the second input of the operational amplifier is a positive input, the first output of the operational amplifier is a negative output, and the second output of the operational amplifier is a positive output.
Claim 10
Dependent Claim
24 words
The circuit of claim 1 further comprising a switch coupled between the common node and the first and second input of the operational amplifier.
References Cited (Backward Citations)
US4112384A
Cited
US4354250A
Cited
US4468749A
Cited
US4404525A
Cited
US4375625A
Cited
US4453258A
Cited
US4438354A
Cited
US4441082A
Cited
US4446438A
Cited
US4441080A
Cited
US4555668A
Cited
US4634997A
Cited
US4691172A
Cited
US4849662A
Cited
US4806874A
Cited
US5087899A
Cited
US5028893A
Cited
US5157323A
Cited
US5608345A
Cited
US5784016A
Cited
US5852416A
Cited
US5841310A
Cited
US5929796A
Cited
US5990819A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-09-10 | 2005-03-12 | 2005-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-09-10 | 2009-03-12 | 2009-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-09-10 | 2013-03-12 | 2013-09-11 | $7700.00 | Window Closed / Lapsed |