EP0454303A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electronic data format conversion system and method
Assignee: Texas Instruments Inc
•
Filing: 1991-03-26
•
Granted: —
•
Expires: 2011-03-26
Abstract
Abstract There is disclosed a temperature compensated reference voltage generation circuit 30 and method adapted to maintain a specific temperature/voltage relationship. The circuit 30 is designed such that it can easily be adapted to switch between different voltage temperature requirements simply by adjusting the parameters of a few circuit elements. The circuit relies upon three different current generators 40, 50, 31, each performing a different function. There is also disclosed a circuit and method for converting on/off logic signals from one medium to on/off signals useful in a different medium. The circuit is particularly adapted to translate from negative voltage levels to positive voltage levels. The circuit includes voltage control levels for precisely controlling voltage as a function of temperature, all while only using positive voltage levels on the conversion circuit.
Inventors
- 👤 Frederick A. Sammet
- 👤 Kathleen M. Adams
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 04:15
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/38; G06F13/382; G06F13/387
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
100 words
A reference voltage generation circuit having precisely controllable temperature/voltage characteristics, said circuit comprising: an output for supplying said voltage, a first current source for supplying a current independent of supply voltage, a first current for supplying a constant voltage, said first circuit dependent upon current from said first current source, a second current source for supplying current which increases as temperature increases, a third current source for supplying current which decreases as temperature increases, and circuitry for mixing said second and third currents to produce a resulting voltage at said output having controllable voltage characteristics as a function of temperature.
Claim 2
Dependent Claim
15 words
The circuit set forth in claim 1 wherein said mixing circuit includes a resistive element.
Claim 3
Dependent Claim
68 words
The circuit set forth in claim 2 wherein said second current source includes a plurality of parallel connected transistors, each having their bases, collectors and emitters, respectively connected in common, and wherein the common emitters are resistively connected to ground. The number of parallel connected transistors and resistors is variable depending upon the degree of change that is required and the magnitude of the desired output voltage level.
Claim 4
Dependent Claim
41 words
The circuit set forth in claim 2 wherein said third current source includes at least one resistor, the value of which is variable depending upon the degree of change that is required and the magnitude of the desired output voltage level.
Claim 5
Dependent Claim
27 words
The circuit set forth in claim 1 further comprising circuitry for remotely modifying the current derived from said second current source and from said third current source.
Claim 6
Independent Claim
90 words
A method of providing a reference voltage having precisely controllable temperature/voltage characteristics, said method comprising the steps of supplying said voltage on an output, supplying a first current independent of supply voltage, supplying a constant voltage, said current voltage dependent upon current from said first current supplying step, supplying a second current which increases as temperature increases, supplying a third current which decreases as temperature increases, and mixing said second and third currents to produce a resulting voltage at said output having controllable voltage characteristics as a function of temperature.
Claim 7
Dependent Claim
15 words
The method set forth in claim 6 wherein said mixing step includes a resistive element.
Claim 8
Dependent Claim
65 words
The method set forth in claim 7 wherein said second current supplying step includes the step of establishing a plurality of parallel connected transistors, each having their bases, collectors and emitters, respectively connected in common, and wherein the number of parallel connected transistors and resistors is variable depending upon the degree of change that is required and the magnitude of the desired output voltage level.
Claim 9
Dependent Claim
138 words
A circuit for converting from first logic on/off input levels to second logic output levels, said circuit including only positive voltages with respect to ground, said circuit comprising: a threshold reference voltage measured positive with respect to ground, said reference voltage used to set the level for switching between said on and off levels; an output node for driving said on/off output levels; a control switch biased continuously in the conducting condition, said switch operable for providing high and low current to said output node; and circuitry for quickly changing said control switch between said high and low current conditions dependent upon whether or not the voltage condition presented to said circuit input is above or below said reference voltage where above represents the logical on condition and below represents the logical off condition of an input signal.
Claim 10
Dependent Claim
56 words
The circuit set forth in claim 9 wherein said quickly changing circuitry includes: a load control switch operable for controlling said control switch; and wherein the threshold between said on and off condition of said input signal is controlled by said value of said threshold reference voltage and the switching point of said load control switch.
Claim 11
Dependent Claim
34 words
The circuit set forth in claim 10 wherein said load control switch is a gated transistor and wherein said threshold voltage is applied to the gate of said transistor via a current mirror circuit.
Claim 12
Dependent Claim
45 words
The circuit set forth in claim 10 further comprising: circuitry for establishing a specific voltage level at said circuit output without regard to said input signal; and circuitry for allowing said input signal to bypass said circuit and be presented directly to said CMOS circuit.
Claim 13
Dependent Claim
130 words
A circuit for converting from ECL logic on/off input levels to CMOS logic output levels, said circuit including only positive voltages with respect to ground, said circuit comprising: a threshold reference voltage measured positive with respect to ground, said reference voltage used to set the level for switching between said on and off levels; a control transistor switch biased continuously in the conducting condition, the emitter of said transistor resistively connected to the input of said circuit; an output control node for driving the on/off output levels, said output node connected to the collector of said control transistor; and circuitry for quickly changing said control node from high to low dependent upon whether or not the voltage condition presented to said circuit input is above or below said reference voltage.
Claim 14
Dependent Claim
122 words
The circuit set forth in claim 13 wherein said circuitry comprises: a pair of transistor connected base to base and emitter to emitter, said base coupled to said input such that a change in input signal causes a large change in current at the collector of a first one of said transistors; a load transistor connected to the collector of said control transistor and to said output node, said load transistor acting as a resistive path for said control transistor while in one state and acting as a high current source for said control transistor in a second state, said load transistor operable under control of said current change from said first transistor for quickly changing from one state to the other.
Claim 15
Dependent Claim
48 words
The circuit set forth in claim 14 further comprising: a current mirror consisting of a pair of transistors, one of which is said load transistor; and wherein said current change from said first transistor is communicated to said load transistor via the other transistor of said current mirror.
Claim 16
Dependent Claim
55 words
The circuit set forth in claim 15 further comprising: a voltage compensation circuit for removing the effects of voltage variations in said positive supply voltage so as to maintain constant the current flowing through said load transistor, said compensation circuit including a transistor connected from said supply voltage to the gate of said load transistor.
Claim 17
Dependent Claim
45 words
The circuit set forth in claim 14 further comprising: circuitry for establishing a specific voltage level at said circuit output without regard to said input signal; and circuitry for allowing said input signal to bypass said circuit and be presented directly to said CMOS circuit.
Claim 18
Independent Claim
144 words
The method of converting from first logic on/off input levels to second logic output levels while using only positive voltages with respect to ground, said method comprising the steps of: establishing a threshold reference voltage measured positive with respect to ground, said reference voltage used to set the level for switching between said on and off levels; driving said on/off output levels from an output node; biasing a control switch so that it is continuously in the conducting condition, said switch operable for providing high and low current to said output node; and quickly changing said control switch between said high and low current conditions dependent upon whether or not the voltage condition presented to said circuit input is above or below said established reference voltage, wherein above represents the logical on condition and below represents the logical of condition of an input signal.
Claim 19
Dependent Claim
55 words
The method set forth in claim 18 wherein said quickly changing step includes: controlling said control switch from a load control switch; and wherein the threshold between said on and off condition of said input signal is controlled by said value of said threshold reference voltage and the switching point of said load control switch.
Claim 20
Dependent Claim
40 words
The method set forth in claim 19 wherein said load control switch is a gated transistor and wherein said method further includes the step of: applying said threshold voltage to the gate of said transistor via a current mirror circuit.
Claim 21
Dependent Claim
102 words
The method set forth in claim 20 wherein said circuitry further comprises: a pair of transistors connected base to base and emitter to emitter, said base coupled to said input such that a change in input signal causes a large change in current at the collector of a first one of said transistors, and wherein said method further includes the step of: connecting said load control switch to said transistor pair and to said threshold voltage such that said load control switch operates under control of said current change from said first transistor for quickly changing from one state to the other.
Claim 22
Independent Claim
122 words
The method of converting from ECL logic on/off input levels to CMOS logic output levels, said method including the steps of: establishing a threshold reference voltage measured positive with respect to ground, said reference voltage used to set the level for switching between said on and off levels; continuously biasing a control transistor switch in the conducting condition, the emitter of said transistor resistively connected to the input of said circuit; driving the on/off output levels from an output control node, said output node connected to the collector of said control transistor; and quickly changing said control node from high to low dependent upon whether or not the voltage condition presented to said circuit input is above or below said reference voltage.
Claim 23
Dependent Claim
130 words
The method set forth in claim 22 wherein there is a pair of transistors connected base to base and emitter to emitter, said base coupled to said input such that a change in input signal causes a large change in current at the collector of a first one of said transistors; and a load transistor connected to the collector of said control transistor and to said output node, said load transistor acting as a resistive path for said control transistor while in one state and acting as a high current source for said control transistor in a second state, and wherein said method includes the step of: operating said load transistor operable under control of said current change from said first transistor for quickly changing from one state to another.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.