摘要:
A balanced voltage-to-current converter has two cells (24A; 24B). Each cell has a first input terminal (6A; 6B) coupled to a first current source (4A; 4B) via a diode-connected first transistor (T1A; T1B) and to an output terminal (18A; 18B) via the main current path of a third transistor (T3A; T3B), and a second input terminal (10A; 10B) coupled to a second current source (14A; 14B) via the main current path of a second transistor (T2A; T2B). The control electrode of the third transistor (T3A; T3B) is connected to the node (8A; 8B) between the second current source (14A; 14B) and the second transistor (T2A; T2B). The first input terminal of one of cell is connected to the second input terminal of the other cell and vice versa . The quiescent current through the third transistor (T3A; T3B) is controlled by a differential amplifier (40A; 40B) which compares the voltage difference between the control electrode and the first main electrode of the third transistor (T3A; T3B) with a reference voltage (44A; 44B) which is representative of the current through the third transistor (T3A; T3B). The output signals of the differential amplifiers (40A; 40B) are summed in an adder (50) and are applied to control inputs (54A; 54B) of the second current sources (14A; 14B).
摘要:
Un amplificateur de puissance comprend un étage d'entrée comportant un amplificateur entièrement différentiel avec des entrées et des sorties différentielles, et un circuit de contrôle du retour fonctionnant en boucle fermée et à haute impédance séparant les signaux de contrôle de retour en boucle fermée des sorties différentielles. L'étage de sortie de chaque sortie différentielle de l'étage d'entrée comprend un amplificateur de classe AB ayant des suiveurs de source s'interfaçant avec l'amplificateur entièrement différentiel. Un circuit de contrôle de la tension de sortie fonctionnant en mode commun maintient la tension de sortie en mode commun de l'amplificateur de classe AB à un niveau voulu. Un régulateur de courant de repos comprend un circuit reproduisant le comportement de l'un des suiveurs de source pour dériver un signal de régulation en maintenant le courant de repos des transistors de sortie à une valeur désirée.
摘要:
La présente invention concerne un amplificateur CMOS à entrée et sortie différentielles. L'étage d'entrée comprend deux branches dont chacune comprend un transistor d'entrée (MN1, MN2). Un étage de contre-réaction de mode commun comprend une charge (MP23) connectée à la tension d'alimentation haute, un premier transistor (MP21) connecté entre cette charge et la borne commune des transistors d'entrée, ce premier transistor étant polarisé à la tension de mode commun souhaitée (VCM), et un deuxième transistor (MP22) connecté entre la charge et la tension d'alimentation basse (Vss) et dont la grille est reliée à un potentiel (VM) indicatif de la tension moyenne de l'étage de sortie. Un transistor supplémentaire (MN31, MN32) est en parallèle sur chacun des transistors d'entrée (MN1, MN2). Chaque transistor supplémentaire a sa grille à la tension de mode commun souhaitée (VCM).
摘要:
La présente invention concerne un dispositif de compensation de déséquilibre d'un étage d'entrée (10) à deux branches de sortie de courant dont une première (D+) est reliée à l'entrée d'un vrai étage (12) dérivant de cette première branche un courant parasite (I O ). Le dispositif comprend un faux étage (34) dérivant un courant de compensation (I O /K) de valeur K (K>1) fois inférieure à la valeur du courant parasite, ce courant de compensation étant amplifié par un amplificateur (36) de gain K avant d'être dérivé de la deuxième branche de sortie (D-) de l'étage d'entrée.
摘要:
A temperature compensated ECL gate (20) with each gate circuit resistance formed by a pair of opposite polarity temperature coefficient resistors. A first gate transistor element (Q1) and a second gate transistor element (Q2) coupled at a common emitter coupling (12) provide alternative collector current paths from high potential (V CC ) through a first gate transistor collector path with collector resistance (R11,R12) and a gate transistor collector path with collector resistance (R21,R22). A current source transistor element (Q3) is coupled between the common emitter coupling (12) of the gate transistor elements and low potential (V EE ) through current source resistance (R31,R32). The resistances of the ECL gate each include a positive temperature coefficient silicon first resistor (R11,R21,R31) and a negative temperature coefficient low capacitance polysilicon second resistor coupled (R12,R22,R32) in series. The sum of the resistances of the first and second resistors is selected to providing the respective circuit resistance of the ECL gate and the ratio of the resistances of the first and second resistors is selected according to the temperature characteristics of the current source voltage generator and the temperature characteristics of the first and second resistors for substantial temperature compensation of the gate current and signal voltage swing over a specified temperature range. The temperature compensating pair of opposite polarity temperature coefficient resistors is also applicable for temperature compensation at active nodes of TTL and STL circuits.
摘要:
The improved operational amplifier stages are an input (601), a gain (603) and an output stage (605). The input stage (601) has a differential buffer amplifier (Q101,Q102,R1A,R1B,R2A,R2B) connected to a transconductance section (Q1,Q2) for converting a differential voltage signal to a current signal. The input stage (601) is operable within a range of differential voltage signals, the range including common mode voltage signals at or beyond the negative supply rail (7). The gain stage (603) has two cascaded transistors (Q3,Q4). The base of the first transistor (Q4) is connected to the emitter of the second transistor (Q3) through an integrating capacitor (C1). The capacitor (C1) is further connected through a resistor (R3) to the negative supply rail (7). The output stage (605) has a driving amplifier and two common emitter output transistors (Q106,Q9). One output transistor (Q106) is driven by the amplifier through two current mirrors (Q103A,Q103B;Q6,Q7) the output of the second current mirror being compared to a reference current source. The other output transistor (Q9) is driven directly by the amplifier.
摘要:
The improved operational amplifier stages are an input (601), a gain (603) and an output stage (605). The input stage (601) has a differential buffer amplifier (Q101,Q102,R1A,R1B,R2A,R2B) connected to a transconductance section (Q1,Q2) for converting a differential voltage signal to a current signal. The input stage (601) is operable within a range of differential voltage signals, the range including common mode voltage signals at or beyond the negative supply rail (7). The gain stage (603) has two cascaded transistors (Q3,Q4). The base of the first transistor (Q4) is connected to the emitter of the second transistor (Q3) through an integrating capacitor (C1). The capacitor (C1) is further connected through a resistor (R3) to the negative supply rail (7). The output stage (605) has a driving amplifier and two common emitter output transistors (Q106,Q9). One output transistor (Q106) is driven by the amplifier through two current mirrors (Q103A,Q103B;Q6,Q7) the output of the second current mirror being compared to a reference current source. The other output transistor (Q9) is driven directly by the amplifier.