Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
293 words
Differential mixer (DM) coupled between a first (VCC) and a second (GND) voltage supply terminal for multiplying a first differential input voltage supplied at a first differential voltage input (LO) with a second differential input voltage supplied at a second differential voltage input (VIN), said differential mixer (DM) including a cross-connected pair of differential amplifiers (A; B) responsive to said first differential voltage input and coupled between said first (VCC) voltage supply terminal and a differential pair of mixing input terminals (J1; J2) to which are also coupled a voltage-to-current converter means (VIC) and a current source (I1; I2), said current source including two identical parallel current branches, each connected between distinct differential amplifiers (A; B) via a distinct mixing input terminal (J1; J2) and said second (GND) voltage supply terminal, said parallel current branches each comprising a series connection of a transistor (T1; T2) and a resistor (R5; R7) and said voltage-to-current converter means responsive to said second differential voltage input for converting said second differential input voltage to a differential current (INN) supplied to said differential mixing input terminals, said voltage-to-current converter means including a differential cascode circuit of transistors (P1; P2) having input terminals (J3; J4) to which said second differential voltage input are connected via resistors (RI1; RI2), output terminals connected to said mixing input terminals which are current output terminals (TI1; TI2), and control terminals to which a constant reference voltage terminal (VCC/2) is coupled, said voltage-to-current converter means further including a first pair of constant current sources (PB1, PB2) coupling said first (VCC) voltage supply terminal to the input terminals of said transistors, and a second pair of constant current sources (NB1, NB2) coupling the output terminals of said transistors to said second (GND) voltage supply terminal.
Claim 2
Dependent Claim
293 words
Differential mixer (DM) coupled between a first (VCC) and a second (GND) voltage supply terminal for multiplying a first differential input voltage supplied at a first differential voltage input (LO) with a second differential input voltage supplied at a second differential voltage input (VIN), said differential mixer (DM) including a cross-connected pair of differential amplifiers (A; B) responsive to said first differential voltage input and coupled between said first (VCC) voltage supply terminal and a differential pair of mixing input terminals (J1; J2) to which are also coupled a voltage-to-current converter means (VIC) and a current source (I1; I2), said current source including two identical parallel current branches, each connected between distinct differential amplifiers (A; B) via a distinct mixing input terminal (J1; J2) and said second (GND) voltage supply terminal, said parallel current branches each comprising a series connection of a transistor (T1; T2) and a resistor (R5; R7) and said voltage-to-current converter means responsive to said second differential voltage input for converting said second differential input voltage to a differential current (INN) supplied to said differential mixing input terminals, said voltage-to-current converter means including a differential cascode circuit of transistors (P1; P2) having input terminals (J3; J4) to which said second differential voltage input are connected via resistors (RI1; RI2), output terminals connected to said mixing input terminals which are current output terminals (TI1; TI2), and control terminals to which a constant reference voltage terminal (VCC/2) is coupled, said voltage-to-current converter means further including a first pair of constant current sources (PB1, PB2) coupling said first (VCC) voltage supply terminal to the input terminals of said transistors, and a second pair of constant current sources (NB1, NB2) coupling the output terminals of said transistors to said second (GND) voltage supply terminal.
Claim 3
Dependent Claim
50 words
Differential mixer according to claim 1, characterized in that said constant reference voltage terminal (VCC/2) is coupled to the control terminal of each of said transistors (P1; P2) via a distinct operational amplifier (O1; O2) of which another input is connected to the input terminal (J3; J4) of said transistor.
Claim 4
Dependent Claim
62 words
Differential mixer according to claim 1, characterized in that said first differential input voltage has a relatively high frequency, in that said second differential input voltage has a relatively low frequency, and in that said cross-connected pair of differential amplifiers (A; B) is coupled to said differential pair of mixing input terminals. (J1; J2) via low pass filters (R3, C1; R4, C2).
Claim 5
Dependent Claim
44 words
Differential mixer according to claim 1, characterized in that said transistors (P1; P2) of said voltage-to-current converter means (VIC) are MOS transistors and in that said input (J3; J4), output and control terminals are the source, drain and gate electrodes of said transistors respectively.
Claim 6
Dependent Claim
21 words
Differential mixer according to claim 1, characterized in that said cross-connected pair of differential amplifiers (A; B) includes silicon bipolar transistors.
Claim 7
Dependent Claim
52 words
Differential mixer according to claim 1, characterized in that said differential mixer (DM) includes, coupled between said first (VCC) and said second (GND) voltage supply terminal, a series connection of load resistors (R1; R2), said cross-connected pair of differential amplifiers (A; B), said differential mixing input (J1; J2) and said current source.
Claim 8
Dependent Claim
34 words
Differential mixer according to claim 6, characterized in that low pass filters (R3, C1; R4, C2) are located between said cross-connected pair of differential amplifiers (A; B) and said differential mixing input (J1; J2).
Claim 9
Dependent Claim
62 words
Differential mixer according to the claim 4, characterized in that said cross-connected pair of differential amplifiers (A; B) and said current source (I1; I2) are integrated in a first electronic chip, and said voltage-to-current converter means (VIC) is integrated in a second electronic chip, said first and second electronic chips being interconnected via said differential pair of mixing input terminals (J1; J2).
Claim 10
Dependent Claim
62 words
Differential mixer according to the claim 5, characterized in that said cross-connected pair of differential amplifiers (A; B) and said current source (I1; I2) are integrated in a first electronic chip, and said voltage-to-current converter means (VIC) is integrated in a second electronic chip, said first and second electronic chips being interconnected via said differential pair of mixing input terminals (J1; J2).