Patent EP0189564A2 successfully refreshed from Google Patents.
EP0189564A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
High to low transition speed up circuit for TTL-type gates
Assignee: Texas Instruments Inc
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Filing: 1985-12-10
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Granted: —
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Expires: 2005-12-10
Abstract
Abstract The specification discloses an input transistor (14) which Is variable between high and low impedance states in response to input voltage transitions at terminal 10. An output transistor (16) is coupled to the input transistor (14) and is responsive to an input transition at terminal 10 for changing impedance states. Circuitry including a speed up transistor (44) is coupled between the input transistor (14) and output transistor (16) for applying added current to the output transistor (16) to speed the change of impedance stste. The circuitry applies added current to output transistor (15) until the output voltage at terminal (18) falls below twice the base-emitter voltage of the output transistor (16).
Inventors
- 👤 Bobby D. Strong
- 👤 Kevin M. Ovens
- 👤 Robert C. Martin
- 👤 James F. Salzman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 21:04
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/02; H03K19/08; H03K19/082; H03K19/088; H03K19/01; H03K19/013; H03K19/0136; H03K19/0823; H03K19/0826
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
82 words
An improved transition speed up circuit comprising: an input transistor for receiving input voltage transitions; an output transistor coupled to said input transistors and responsive to a voltage transition at said input transistor to change state; means coupled between said input and output transistors for applying added current to said output transistor to speed up said change of state, said means applying added current until the output voltage across said output transistor falls below twice the base-emitter voltage of said output transistor.
Claim 2
Dependent Claim
82 words
An improved transition speed up circuit comprising: an input transistor for receiving input voltage transitions; an output transistor coupled to said input transistors and responsive to a voltage transition at said input transistor to change state; means coupled between said input and output transistors for applying added current to said output transistor to speed up said change of state, said means applying added current until the output voltage across said output transistor falls below twice the base-emitter voltage of said output transistor.
Claim 3
Dependent Claim
16 words
The speed up circuit of Claim 1 wherein said means provides amplification to said added current.
Claim 4
Dependent Claim
13 words
The speed up circuit of Claim 2 wherein said means includes a transistor.
Claim 5
Dependent Claim
66 words
The speed up circuit of Claim 1 wherein said means includes a pair of unidirectional conductive elements connected in series and connected between said input and output transistors, and a speed up transistor connected between the junction of said unidirectional conductive elements and said output transistor, conduction of said input transistor and speed up transistor causing said added current to be applied to said output transistor.
Claim 6
Dependent Claim
48 words
The speed up circuit of Claim 1 wherein said means includes a unidirectional conductive element connected at one terminal to said input transistor and connected at a second terminal to a Schottky clamped transistor, said Schottky clamped transistor connected across the input and output of said output transistor.
Claim 7
Dependent Claim
27 words
The speed up circuit of Claim 1 wherein said means includes a Schottky clamped transistor connected between said input transistor and the output of said output transistor.
Claim 8
Dependent Claim
26 words
The speed up circuit of Claim 6 and further comprising second means connected to said Schottky clamped transistor to provide a high impedance third state output.
Claim 9
Dependent Claim
36 words
The speed up circuit of Claim 7 wherein said second means comprises a diode connected at its anode to the base of said Schottky clamped transistor, the cathode of said diode comprising said third state output.
Claim 10
Dependent Claim
41 words
The speed up circuit of Claim 7 wherein said second means a second Schottky clamped transistor connected at its collector to the base of said Schottky clamped transistor, the emitter of said second Schottky clamped transistor comprising said third state output.
Claim 11
Dependent Claim
95 words
An improved transition speed up circuit comprising: an input for receiving a low or a high input voltage; an input transistor coupled to said input for becoming conductive upon a voltage transition at said input; an output transistor coupled to said input transistor; at least one unidirectional conductive element connected between said input and said output transistor; a speed up transistor connected to said unidirectional conductive element and the input of said output transistor; and said output transistor changing states in response to current applied from conduction of said transistor and said speed up transistor.
Claim 12
Dependent Claim
95 words
An improved transition speed up circuit comprising: an input for receiving a low or a high input voltage; an input transistor coupled to said input for becoming conductive upon a voltage transition at said input; an output transistor coupled to said input transistor; at least one unidirectional conductive element connected between said input and said output transistor; a speed up transistor connected to said unidirectional conductive element and the input of said output transistor; and said output transistor changing states in response to current applied from conduction of said transistor and said speed up transistor.
Claim 13
Dependent Claim
39 words
The speed up circuit of Claim 10 and further comprising a second unidirectional conductive element connected in series with said at least one unidirectional conductive element, said speed up transistor connected to the junction of said unidirectional conductive elements.
Claim 14
Dependent Claim
50 words
The speed up circuit of Claim 11 wherein said pair of unidirectional conductive elements and speed up transistor provide an AND function by providing additional turn on current to said output transistor when both said input voltage and the output of said output transistor are of the same voltage condition.
Claim 15
Dependent Claim
24 words
The speed up circuit of Claim 10 and further comprising: means connected to said input transistor for providing a high impedance third state output.
Claim 16
Dependent Claim
18 words
The speed up circuit of Claim 10 wherein said at least one unidirectional conductive element comprises a diode.
Claim 17
Dependent Claim
17 words
The speed up circuit of Claim 11 wherein said second unidirectional conductive element comprises a Schottky diode.
Claim 18
Dependent Claim
122 words
An improved transition speed up circuit comprising: an input transistor having a base connected to receive either a low input voltage or a high input voltage; an output transistor having a base coupled to the emitter of said input transistor, the collector of said output transistor providing an output voltage; a speed up transistor having an emitter connected to the collector of said input transistor and having a collector connected to the collector of said output transistor; a high input voltage applied to said base of said input transistor causing speed up current to be applied from said speed up transistor to said base of said output transistor to speed up the conduction of said output transistor and vary said output voltage.
Claim 19
Dependent Claim
122 words
An improved transition speed up circuit comprising: an input transistor having a base connected to receive either a low input voltage or a high input voltage; an output transistor having a base coupled to the emitter of said input transistor, the collector of said output transistor providing an output voltage; a speed up transistor having an emitter connected to the collector of said input transistor and having a collector connected to the collector of said output transistor; a high input voltage applied to said base of said input transistor causing speed up current to be applied from said speed up transistor to said base of said output transistor to speed up the conduction of said output transistor and vary said output voltage.
Claim 20
Dependent Claim
38 words
The improved transition speed up circuit of Claim 16 wherein said speed up transistor applies speed up current until the voltage at the collector of said output transistor falls below twice the base-emitter voltage of said input transistor.
Claim 21
Dependent Claim
19 words
The improved transition speed up circuit of Claim 16 wherein said speed up transistor comprises a Schottky clamped transistor.
Claim 22
Dependent Claim
74 words
The improved transition speed up circuit of Claim 16 and further comprising: a first diode connected at its anode to the base of said input transistor; a second diode connected at its anode to the collector of said input transistor; a third diode connected at its anode to the base of said speed up transistor; and the cathodes of said first, second and third diodes interconnected to form a third high impedance state output.
Claim 23
Dependent Claim
77 words
The improved transition speed up circuit of Claim 16 and further comprising: a first diode connected at its anode to the base of said input transistor; a second diode connected at its anode to the collector of said input transistor; and a transistor having a collector connected to the base of said speed up transistor and having an emitter tied to the cathodes of said first and second diodes to form a third high impedance state output.
Claim 24
Dependent Claim
67 words
The improved transition speed up circuit of Claim 20 and further comprising: a fourth transistor having an emitter connected to said collector of said output transistor; a fifth transistor having an emitter connected to the base of said fourth transistor and having a collector connected to the collector of said fourth transistor; and the base of said fifth transistor connected to the collector of said input transistor.
Claim 25
Dependent Claim
132 words
An improved transition speed up circuit comprising: an input transistor having a base for receiving either a low input voltage or a high input voltage; an output transistor having a base connected to the emitter of said input transistor, the collector of said output transistor providing an output voltage; a diode connected at its cathode to said base of said input transistor; a speed up transistor having a base connected to the anode of said diode, the emitter of said speed up transistor connected to said base of said output transistor; and said speed up transistor becoming conductive upon a high input voltage being applied to said base of said input transistor, said speed up transistor maintaining conduction until said output voltage falls below twice the base-emitter voltage of said output transistor.
Claim 26
Dependent Claim
132 words
An improved transition speed up circuit comprising: an input transistor having a base for receiving either a low input voltage or a high input voltage; an output transistor having a base connected to the emitter of said input transistor, the collector of said output transistor providing an output voltage; a diode connected at its cathode to said base of said input transistor; a speed up transistor having a base connected to the anode of said diode, the emitter of said speed up transistor connected to said base of said output transistor; and said speed up transistor becoming conductive upon a high input voltage being applied to said base of said input transistor, said speed up transistor maintaining conduction until said output voltage falls below twice the base-emitter voltage of said output transistor.
Claim 27
Dependent Claim
24 words
The speed up circuit of Claim 22 wherein the collector of said speed up transistor is connected to said collector of said output transistor.
Claim 28
Dependent Claim
41 words
The speed up circuit of Claim 22 and further comprising: an input diode connected at its anode to said base of said input transistor and further connected at its cathode to the cathode of said diode to receive said input voltage.
Claim 29
Dependent Claim
74 words
The speed up circuit of Claim 22 and further comprising: a second diode connected at its anode to said base of said speed up transistor and connected at its cathode to said collector of said output transistor; and said diode and said second diode providing an AND function by providing turn on current to said base of said output transistor when both said input voltage and said output voltage have a high voltage level.
Claim 30
Dependent Claim
15 words
The speed up circuit of Claim 25 wherein said second diode comprises a Schottky diode.
Claim 31
Dependent Claim
71 words
The speed up circuit of Claim 22 and further comprising: a second diode connected at its anode to said base of said input transistor; a third diode connected at its anode to said anode of said diode; a fourth diode connected at its anode to the collector of said input transistor; and the cathodes of said second, third and fourth diodes connected together to form a third high impedance state output.
References Cited (Backward Citations)
No citation records indexed.
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