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US4568844A Expired / Lapsed US ⏱️ 0.0 years remaining

Field effect transistor inverter-level shifter circuitry

Assignee: Nokia Bell Labs
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Filing: 1983-02-17
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Granted: 1986-02-04
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Expires: 2003-02-17
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Abstract

Abstract A field effect transistor inverter-level shifter circuit which accepts TTL input level signals and generates MOS output level signals consists of the series combination of a load device, an enhancement mode transistor, and a depletion mode transistor. The gates of the enhancement and depletion mode transistors are connected to an input terminal. The source of the enhancement transistor is connected to the drain of the depletion transistor. The depletion transistor acts to control the potential of the source of the enhancement transistor so as to allow it to tolerate worse case TTL input potential "0" levels while not becoming more than only weakly biased on.

Inventors

  • 👤 Kevin J. O'Connor

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 16:35
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/02; H03K19/08; H03K19/094; H03K19/0944; H03K19/09441; H03K19/09443; H03K19/09445; H03K19/0175; H03K19/0185; H03K19/018507

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 120 words
Circuitry comprising: a load device having first and second terminals, the first terminal being connectable to a first potential source and the second terminal serving as an output node; a first field effect transistor having its drain terminal coupled to the second terminal of the load device and having its gate terminal conductively ohmically coupled to a circuitry input terminal; and a second field effect transistor having its drain terminal coupled to, and only to, the source terminal of the first transistor, and having its gate terminal coupled to the gate terminal of the first transitor, and having its source terminal connectable to a second potential source, the first transistor being enhancement mode and the second transistor being depletion mode.
Claim 2
Dependent Claim 120 words
Circuitry comprising: a load device having first and second terminals, the first terminal being connectable to a first potential source and the second terminal serving as an output node; a first field effect transistor having its drain terminal coupled to the second terminal of the load device and having its gate terminal conductively ohmically coupled to a circuitry input terminal; and a second field effect transistor having its drain terminal coupled to, and only to, the source terminal of the first transistor, and having its gate terminal coupled to the gate terminal of the first transitor, and having its source terminal connectable to a second potential source, the first transistor being enhancement mode and the second transistor being depletion mode.
Claim 3
Dependent Claim 24 words
The circuitry of claim 1 wherein the load device is a third field effect transistor with its source terminal coupled to its gate terminal.
Claim 4
Dependent Claim 42 words
The circuitry of claim 2 wherein the third field effect transistor is a depletion mode transistor which has its gate and source terminals coupled to the drain of the first transistor and has its drain terminal connectable to the first potential source.
Claim 5
Dependent Claim 23 words
The circuitry of claim 3 further comprising an inverter having an input terminal coupled to the output node and having an output terminal.
Claim 6
Dependent Claim 69 words
The circuitry of claim 4 wherein: the inverter comprises fourth and fifth field effect transistors which are a depletion mode and an enhancement mode transistor, respectively, and the gate terminal of the fifth transistor serves as the input terminal of the inverter, and the gate and source terminals of the fourth transistor and the drain terminal of the fifth transistor are coupled to the output terminal of the inverter.
Claim 7
Dependent Claim 16 words
The circuitry of claim 5 wherein all transistors are n-channel type insulated gate field effect transistors.
Claim 8
Dependent Claim 19 words
The circuitry of claim 6 wherein the fifth transistor is enhancement mode and the fourth transistor is deletion mode.
Claim 9
Dependent Claim 16 words
The circuitry of claim 5 wherein all transistors are p-channel type insulated gate field effect transistors.
Claim 10
Dependent Claim 19 words
The circuitry of claim 8 wherein the fifth transistor is enhancement mode and the fourth transistor is deletion mode.
Claim 11
Dependent Claim 32 words
The circuitry of claim 5, wherein the first, second, and fifth transistors are n-channel insulated gate field effect transistors, and the third and fourth transistors are p-channel insulated gate field effect transistors.
Claim 12
Dependent Claim 32 words
The circuitry of claim 5 wherein the first, second, and fifth transistors are p-channel insulated gate field effect transistors, and the third and fourth transistors are n-channel insulated gate field effect transistors.
Claim 13
Dependent Claim 162 words
In a level-shifting circuit (a) first and second field effect transistors, each having a separate gate, source, and drain terminal, the second transistor having its drain terminal coupled to, and only to, the source terminal of the first transistor, and the second transistor having its source terminal connectable to a potential source; (b) a load device; (c) conducting means for coupling the drain terminal of the first transistor to the load device, whereby a first node is formed between the load device and the first transistor along the first conducting means, the first transistor being enhancement mode and the second transistor being depletion mode; and (d) a circuit input node, for receiving input signals to be level shifted, conductively ohmically coupled both to the gate terminal of the first transistor and to the gate terminal of the second transistor, whereby in response to the input signals being applied to the circuit input terminal there are developed inverted signals at the first node.
Claim 14
Dependent Claim 162 words
In a level-shifting circuit (a) first and second field effect transistors, each having a separate gate, source, and drain terminal, the second transistor having its drain terminal coupled to, and only to, the source terminal of the first transistor, and the second transistor having its source terminal connectable to a potential source; (b) a load device; (c) conducting means for coupling the drain terminal of the first transistor to the load device, whereby a first node is formed between the load device and the first transistor along the first conducting means, the first transistor being enhancement mode and the second transistor being depletion mode; and (d) a circuit input node, for receiving input signals to be level shifted, conductively ohmically coupled both to the gate terminal of the first transistor and to the gate terminal of the second transistor, whereby in response to the input signals being applied to the circuit input terminal there are developed inverted signals at the first node.
Claim 15
Dependent Claim 18 words
The circuit of claim 12 in which the first and second transistors are insulated gate field effect transistors.
Claim 16
Dependent Claim 22 words
The circuit of claim 13 further comprising an inverter connected for receiving and inverting the inverted signals to produce level-shifted output signals.
Claim 17
Dependent Claim 22 words
The circuit of claim 12 further comprising an inverter connected for receiving and inverting the inverted signals to produce level-shifted output signals.

References Cited (Backward Citations)

US3675144A Cited
US3739194A Cited
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US4096584A Cited
US4109163A Cited
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US4437025A Cited
US4475050A Cited
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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) 1989-02-03 1989-08-05 1990-02-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-02-03 1993-08-05 1994-02-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-02-03 1997-08-05 1998-02-04 $7700.00 Window Closed / Lapsed

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