US4695804A
Expired / Lapsed
US
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Apparatus for generating a multi-frequency signal
Assignee: Siemens AG
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Filing: 1985-07-31
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Granted: 1987-09-22
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Expires: 2005-07-31
Abstract
Abstract An appartus for generating a multi-frequency signal includes a D/A converter, two converter circuits connected to the D/A converter for determining a respective connecting instant, two controlled waveform counters each being connected to a respective one of the converter circuits, a D/A cycle control connected to the converter circuits for monitoring the converter circuits, a sample-and-hold circuit having divider capacitors and being connected to the D/A converter, and holding capacitors connected to the sample-and-hold circuit.
Inventors
- 👤 Artur Bardl
- 👤 Manfred Lindner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:34
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/26; H04M1/30; H04M1/50; H04M1/505
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
115 words
Apparatus for generating a multi-frequency signal, comprising a digital-to-analog converter, two coordinating circuits connected to said D/A converter for providing different frequency analog-wave information to said D/A converter for determining a respective connecting instant, two forward/backward counters driven by different frequencies each being connected for controlling a respective one of said coordinating circuits, a D/A cycle control connected to said coordinating circuits for monitoring time connecting instants of said converter circuits to said D/A converter, a sample-and-hold circuit having at least two divider capacitors and being connected to said D/A converter controlled by said D/A cycle control, and holding capacitors connected to said sample-and-hold circuit, whereby at least two different frequency analog waves are generated.
Claim 2
Dependent Claim
115 words
Apparatus for generating a multi-frequency signal, comprising a digital-to-analog converter, two coordinating circuits connected to said D/A converter for providing different frequency analog-wave information to said D/A converter for determining a respective connecting instant, two forward/backward counters driven by different frequencies each being connected for controlling a respective one of said coordinating circuits, a D/A cycle control connected to said coordinating circuits for monitoring time connecting instants of said converter circuits to said D/A converter, a sample-and-hold circuit having at least two divider capacitors and being connected to said D/A converter controlled by said D/A cycle control, and holding capacitors connected to said sample-and-hold circuit, whereby at least two different frequency analog waves are generated.
Claim 3
Dependent Claim
25 words
Apparatus according to claim 1, wherein said D/A converter includes switched weighted capacitors forming a voltage divider with said divider capacitors of said sample-and-hold circuit.
Claim 4
Dependent Claim
12 words
Apparatus according to claim 1, wherein said divider capacitors have different capacities.
Claim 5
Dependent Claim
12 words
Apparatus according to claim 2, wherein said divider capacitors have different capacities.
Claim 6
Dependent Claim
35 words
Apparatus according to claim 1, including a frequency divider for each frequency for driving a respective forward/backward counter, wherein said holding capacitors can be connected through said D/A cycle control, in dependence on frequency dividers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-09-21 | 1991-03-23 | 1991-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-21 | 1995-03-23 | 1995-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-21 | 1999-03-23 | 1999-09-22 | $7700.00 | Window Closed / Lapsed |