摘要:
Circuit de réception de signaux en provenance d'un équipement connecté par une ligne présentant les caractéristiques définies par la forme EIA RS 232C comprenant un amplificateur différentiel (2) recevant le signal d'entrée d'amplitude divisé par un facteur k par le réseau d'entrée 1. Le seuil de commutation de l'amplificateur (2) est variable et égal à une première valeur pour la commutation sur le flanc de pente positive du signal d'entrée et à une seconde valeur pour la commutation sur le flanc de pente négative. Ce circuit comprend des circuits de détection d'état de l'équipement connecté comprenant un détecteur de niveau (3) et un circuit de décision (4) qui en fonction des sorties du récepteur et du détecteur de niveau (5) engendre un signal d'indication de l'état de l'équipement connecté. Des moyens (5, 6) empêchent que le signal d'indication d'état change de niveau quand le signal d'entrée passe par zéro ou reçoit de brèves impulsions paratites.
摘要:
In input interface circuit (11) for a logic device which has a first transistor (Q1) whose base is supplied with an input signal (VI) and whose emitter is grounded through first and second resistors (R1, R2) and a second transistor (Q2) whose base is supplied with the potential of the node of the first and second resistors (R1, R2) and whose collector sends forth a logic signal. This input interface circuit (11) is further provided with a third resistor (Q3) connected between the second resistor (R2) and ground and a third transistor (Q3) whose current path is connected in parallel to the third resistor (R3) and whose base is connected to the collector of the second transistor (Q2).
摘要:
Beim Übergang von CML-Schaltungen auf TTL-Schaltungen, für die nur eine gemeinsame Versorgungsspannung vorgesehen ist, muß das Bezugspotential gewechselt werden. Zur Transformation der Signale unter Berücksichtigung möglicher Schwankungen der Versorgungsspannung wird erfindungsgemäß eine Stromspiegel-Schaltung eingesetzt. Die Erfindung wird vorzugsweise in hochintegrierten CML-Schaltungsanordnungen mit TTL-kompatiblen Signaleingängen und Signalausgängen angewandt.
摘要:
An output circuit comprising a differential amplifier circuit (Q1, Q2) for providing a pair of complementary output signals corresponding to an input signal (ei) supplied to first and second signal input terminals (T1, T2) thereof, an output transistor (Q3) having a base connected to one output node (A) of the differential amplifier circuit, a collector connected to a first power source potential supply terminal (Vcc), and an emitter connected to a signal output terminal (T3), a current mirror circuit (Q4, Q5) having a current input terminal (X) connected to a current source (I2) and a current output terminal connected to the signal output terminal (T3), and a capacitor (C1) connected between the other output node (B) of the differential amplifier circuit and the current input terminal (X) of the current mirror circuit.
摘要:
A method and apparatus for providing ECL output signals to a capacitative load includes differential amplification of input signals with a first output (14) of a differential amplifier (12) connected for establishing a voltage level between voltage limits V cc and V ee at the output of an output driver in response to variations in the first amplifier output. A pull-down transistor (Q8) has a collector connected to the output driver output (20), an emitter connected to the V ee voltage source, and a base coupled through a boost capacitor (C1) to the second amplifier output (16). A voltage clamp embracing a clamp transistor (Q7) with a base connected to receive a predetermined control voltage has an emitter connected to the boost capacitor (C1) and the pull-down transistor (Q8) base and a collector connected to the V cc voltage source. The clamp transistor (Q7) is operated in Darlington configuration to provide a minimum discharge impedance to the base of the pull-down transistor (Q8). A recovery capacitor (C1) is connected between the clamp transistor (Q7) base and the first amplifier output (16) to speed up the clamp transistor's operation.
摘要:
An input circuit is disclosed, which can be driven by a single power supply, and which can convert an ECL-level input signal falling to a negative voltage into a CMOS-level signal rising to a positive voltage, and can then supply this CMOS-level signal to an inner circuit. The input circuit comprises a transistor (l3), a bias circuit (22, 23, 30-33), and a current-to-voltage converter (24). The emitter of the transistor (l3) is coupled to an input terminal for receiving a signal of a negative potential. The bias circuit (22, 23, 30-33) applies a negative bias voltage to the base of the transistor (l3). The current-to-voltage converter (24) is connected to the collector of the transistor (l3). The converter (24) outputs a signal first falling to a positive level and then rising to another positive level. That is, the input circuit can convert an input signal of a negative level to a signal of a positive level.
摘要:
In the output circuit a signal (S) from an internal circuit is supplied to the gate of an N-channel type MOS transistor (ll), a node (N) of two resistors (l3, l4) connected in series across a power supply terminal (l2) and ground is connected to one end of the MOS transistor (ll). An NPN transistor (l5) is connected at its base to the node (N), at its collector to the power supply terminal (l2) and at its emitter to an output terminal (l6). The positive polarity terminal of a power supply (l7) is connected to the power supply terminal (l2) to supply a positive voltage V CC and the negative polarity terminal of another power supply (l9) is connected through a load resistor (l8) to the output terminal (l6) to supply a negative voltage (-V EE ).