US3825848A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integrated amplifier
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1972-12-18
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Granted: 1974-07-23
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Expires: 1992-12-18
Abstract
Abstract An integrated circuit preamplifier formed on a single substrate divided into regions by insulation frames connected with the microphone of a telephone subset via transistor preamplifier and transistor output amplifiers in different regions to the subscriber''s line. The operating voltages for the amplifiers are received via a conductor which has a decoupling resistor between the points which supply the respective amplifiers, and the portion of such conductor connected to the output amplifier is connected via a decoupling capacitor to a reference potential point.
Inventors
- 👤 O Sternbeck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:48
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/181; H03F3/183; H03F3/187; G; G06; G06F; G06F3/00; G06F3/01; G06F3/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
401 words
An integrated amplifier for connecting a microphone of a telephone set to the subscriber''s line of the telephone set comprising a silicon monolithic wafer divided into separate regions by insulating frames, a first voltage supply conductor on said wafer and extending across at least first and second of said regions, a second voltage supply conductor on said wafer and including a first portion in said first region and a second portion in a third region, a decoupling resistor formed on said wafer and extending from within said first region to within said third region for connecting the first portion of said second voltage supply conductor to the second portion thereof, a pair of output terminals adapted to be connected to the subscriber''s line, the first of said output terminals being connected to said first voltage supply conductor, the second of said output terminals being connected to the free end of the second portion of said second voltage supply conductor, a decoupling capacitor external of said wafer connecting the first portion of said second voltage supply conductor to said first voltage supply conductor, at least a first preamplifier transistor having input, output and reference electrodes formed on said wafer within a fourth region defined by an insulating frame, first and second biasing resistors formed serially on said wafer in said first region and connecting said first and second voltage supply conductors, means formed on said wafer for connecting the junction of said biasing resistors to the input electrode of said transistor, means for connecting the output electrode of said first preamplifier transistor to the first portion of said second voltage supply conductor, means for connecting the reference electrode of said first preamplifier transistor to said first voltage supply conductor, a pair of input terminals adapted to be connected to the microphone of the telephone set, one of said input terminals being connected to the input terminal of said first preamplifier transistor, at least one output transistor amplifier having input, output and reference electrodes, said output transistor amplifier being formed on said wafer within said second region defined by an insulation frame, means formed on said wafer for connecting the reference and output electrodes of said output transistor amplifier to said first and second output terminals, respectively, and coupling means formed on said wafer for connecting the input electrode of said output transistor amplifIer to the output electrode of said first preamplifier transistor.
Claim 2
Dependent Claim
401 words
An integrated amplifier for connecting a microphone of a telephone set to the subscriber''s line of the telephone set comprising a silicon monolithic wafer divided into separate regions by insulating frames, a first voltage supply conductor on said wafer and extending across at least first and second of said regions, a second voltage supply conductor on said wafer and including a first portion in said first region and a second portion in a third region, a decoupling resistor formed on said wafer and extending from within said first region to within said third region for connecting the first portion of said second voltage supply conductor to the second portion thereof, a pair of output terminals adapted to be connected to the subscriber''s line, the first of said output terminals being connected to said first voltage supply conductor, the second of said output terminals being connected to the free end of the second portion of said second voltage supply conductor, a decoupling capacitor external of said wafer connecting the first portion of said second voltage supply conductor to said first voltage supply conductor, at least a first preamplifier transistor having input, output and reference electrodes formed on said wafer within a fourth region defined by an insulating frame, first and second biasing resistors formed serially on said wafer in said first region and connecting said first and second voltage supply conductors, means formed on said wafer for connecting the junction of said biasing resistors to the input electrode of said transistor, means for connecting the output electrode of said first preamplifier transistor to the first portion of said second voltage supply conductor, means for connecting the reference electrode of said first preamplifier transistor to said first voltage supply conductor, a pair of input terminals adapted to be connected to the microphone of the telephone set, one of said input terminals being connected to the input terminal of said first preamplifier transistor, at least one output transistor amplifier having input, output and reference electrodes, said output transistor amplifier being formed on said wafer within said second region defined by an insulation frame, means formed on said wafer for connecting the reference and output electrodes of said output transistor amplifier to said first and second output terminals, respectively, and coupling means formed on said wafer for connecting the input electrode of said output transistor amplifIer to the output electrode of said first preamplifier transistor.
Claim 3
Dependent Claim
169 words
The integrated amplifier of claim 1 wherein the means for connecting the output electrode of said first preamplifier transistor to said second voltage supply conductor is a first collector resistor formed on said wafer in said first region, and wherein said coupling means comprises a second preamplifier transistor having input, output and reference electrodes formed on said wafer within a fifth region defined by an insulating frame, a third biasing resistor formed on said wafer in said first region and connecting the input electrode of said second preamplifier transistor to said first voltage supply conductor, means formed on said wafer for connecting the output electrode of said first preamplifier transistor to the input electrode of said second preamplifier transistor, means formed on said wafer for connecting the reference electrode of said second preamplifier transistor to the first portion of said second voltage supply conductor, and means formed on said wafer for connecting the output electrode of said second preamplifier transistor to the input electrode of said output transistor amplifier.
Claim 4
Dependent Claim
18 words
The integrated amplifier of claim 2 further comprising a further resistor connected in series with said decoupling capacitor.
Claim 5
Dependent Claim
37 words
The integrated amplifier of claim 2 further comprising a full-wave rectifier means having two input connectors for connection to the two wires of the subscriber''s line and two output connectors, respectively, connected to said two output terminals.
Claim 6
Dependent Claim
26 words
The integrated amplifier of claim 4 wherein an accessory impedance connects said first output terminal to one of the output connectors of said full-wave rectifier means.
Claim 7
Dependent Claim
20 words
The integrated amplifier of claim 2 wherein said first and second preamplifier transistors are of complementary npn and pnp types.
Claim 8
Dependent Claim
19 words
The integrated amplifier of claim 2 wherein said output transistor amplifier comprises two transistors connected in a Darlington configuration.
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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) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |