US3789312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Threshold independent linear amplifier
Assignee: International Business Machines Corp
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Filing: 1972-04-03
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Granted: 1974-01-29
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Expires: 1992-04-03
Abstract
Abstract Low level pulses in the order of 100 millivolts or less can be detected and amplified regardless of variations in the voltage required to turn on the active device used in the amplifier. This is achieved by coupling an active device between a capacitor and a capacitively loaded output line, charging the output line to a reference voltage, applying a level setting voltage to the device to turn on the device; charging the capacitor to a voltage substantially equivalent to the level setting voltage to turn off the device while maintaining it such that any input signal superimposed on the level setting voltage will cause the device to again turn on and discharge the capacitively loaded output line thereby amplifying and inverting the superimposed input signal. The invention is particularly useful for sensing random access integrated semiconductor memories. The invention may be employed in either bipolar or field effect transistor technologies.
Inventors
- 👤 L Heller
- 👤 N Vogel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:17
CPC Classifications
G; G11; G11C; G11C7/00; G11C7/06; G11C7/067; H; H03; H03K; H03K19/00; H03K19/02; H03K19/08; H03K19/094; H03K19/096
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
155 words
An amplifier circuit comprising, a three terminal device having a control terminal, a carrier supplying terminal, a carrier receiving terminal and a threshold voltage, a first capacitor having a given capacitive value coupled to the carrier supplying terminal the carrier receiving terminal being coupled to a capacitive load having a capacitive value substantially less than said given value, a reference voltage source means for charging said load and said first capacitor, impedance means coupled between said reference voltage source means and said carrier receiving terminal, means for applying a level setting voltage on the control terminal to charge the first capacitor to a voltage equal to the level setting voltage less the threshold voltage of the device, means for applying a signal voltage on the level setting voltage to turn on the device for discharging said capacitive load through said device to said first capacitor, and an output terminal coupled to the carrier receiving terminal.
Claim 2
Dependent Claim
155 words
An amplifier circuit comprising, a three terminal device having a control terminal, a carrier supplying terminal, a carrier receiving terminal and a threshold voltage, a first capacitor having a given capacitive value coupled to the carrier supplying terminal the carrier receiving terminal being coupled to a capacitive load having a capacitive value substantially less than said given value, a reference voltage source means for charging said load and said first capacitor, impedance means coupled between said reference voltage source means and said carrier receiving terminal, means for applying a level setting voltage on the control terminal to charge the first capacitor to a voltage equal to the level setting voltage less the threshold voltage of the device, means for applying a signal voltage on the level setting voltage to turn on the device for discharging said capacitive load through said device to said first capacitor, and an output terminal coupled to the carrier receiving terminal.
Claim 3
Dependent Claim
16 words
The amplifier circuit of claim 1 wherein there is further provided means for discharging the capacitor.
Claim 4
Dependent Claim
16 words
The amplifier circuit of claim 1 wherein said three terminal devices comprises a Field Effect Transistor.
Claim 5
Dependent Claim
32 words
The amplifier circuit of claim 1 wherein said impedance means comprises a transistor switch between said carrier receiving terminal and said voltage source to selectively isolate the terminal from the voltage source.
Claim 6
Dependent Claim
197 words
An amplifier circuit for compensating for turn-on voltage variations in transistors comprising, a transistor having a control electrode, a carrier supplying electrode, a carrier receiving electrode, and a threshold voltage between said control electrode and said carrier supplying electrode that must be exceeded to place said transistor in a conductive state, a first capacitor coupled between the carrier supplying electrode and ground, a second capacitor coupled to the carrier receiving electrode, a fixed voltage source coupled to the carrier receiving electrode and the second capacitor, means for applying a voltage greater than said threshold voltage on said control electrode for impressing a voltage from said fixed source across the first capacitor to bias the supplying electrode to one threshold voltage below the control electrode, means for decoupling said fixed voltage source from said carrier receiving terminal and said secOnd capacitor, means reactively coupled to the control element for applying an input signal on said voltage on said control electrode, terminal means on the carrier receiving terminal at which the amplified signal may be detected, said signal being amplified proportional to the ratio of the first capacitor to the second capacitor, and means for discharging the first capacitor.
Claim 7
Dependent Claim
197 words
An amplifier circuit for compensating for turn-on voltage variations in transistors comprising, a transistor having a control electrode, a carrier supplying electrode, a carrier receiving electrode, and a threshold voltage between said control electrode and said carrier supplying electrode that must be exceeded to place said transistor in a conductive state, a first capacitor coupled between the carrier supplying electrode and ground, a second capacitor coupled to the carrier receiving electrode, a fixed voltage source coupled to the carrier receiving electrode and the second capacitor, means for applying a voltage greater than said threshold voltage on said control electrode for impressing a voltage from said fixed source across the first capacitor to bias the supplying electrode to one threshold voltage below the control electrode, means for decoupling said fixed voltage source from said carrier receiving terminal and said secOnd capacitor, means reactively coupled to the control element for applying an input signal on said voltage on said control electrode, terminal means on the carrier receiving terminal at which the amplified signal may be detected, said signal being amplified proportional to the ratio of the first capacitor to the second capacitor, and means for discharging the first capacitor.
Claim 8
Dependent Claim
105 words
An amplifier circuit comprising, a device having first and second terminals and a control terminal a capacitor coupled to said first terminal, a capacitive load coupled to said second terminal, means for applying a given control voltage to said control terminal, means for selectively charging said capacitive load to a predetermined voltage and for charging said capacitor through said device, to a voltage sufficient to turn off said device, and means for adding an input signal voltage to the given control voltage on said control terminal of said device to turn on said device for discharging said capacitive load through said device to said capacitor.
Claim 9
Dependent Claim
105 words
An amplifier circuit comprising, a device having first and second terminals and a control terminal a capacitor coupled to said first terminal, a capacitive load coupled to said second terminal, means for applying a given control voltage to said control terminal, means for selectively charging said capacitive load to a predetermined voltage and for charging said capacitor through said device, to a voltage sufficient to turn off said device, and means for adding an input signal voltage to the given control voltage on said control terminal of said device to turn on said device for discharging said capacitive load through said device to said capacitor.
Claim 10
Dependent Claim
33 words
An amplifier circuit as set forth in claim 6 wherein said device has a given threshold voltage and said given control voltage has a magnitude greater than that of said given threshold voltage.
Claim 11
Dependent Claim
24 words
An amplifier circuit as set forth in claim 7 wherein said predetermined voltage has a magnitude substantially greater than that of said control voltage
Claim 12
Dependent Claim
26 words
An amplifier circuit as set forth in claim 6 wherein the capacitance of said capacitive load has a magnitude substantially less than that of said capacitor.
Claim 13
Dependent Claim
27 words
An amplifier circuit as set forth in claim 9 wherein the magnitude of the capacitance of said capacitive load is approximately one-twentieth of that of said capacitor.
Claim 14
Dependent Claim
16 words
An amplifier as set forth in claim 6 further including means for selectively discharging said capacitor.
Claim 15
Dependent Claim
29 words
An amplifier as set forth in claim 6 wherein said charging means includes a source of potential and switching means for selectively coupling said source to said second terminal.
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) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |