Abstract:
A three terminal circuit comprised of two semiconductor transistors of opposite polarity types and two semiconductor diodes. These semiconductors are interconnected so as to provide positive regenerative feedback in a manner which permits achieving highly stable, temperature insensitive circuit characteristics which can be made independent of circuit parameters. The circuit requires no resistors, capacitors or inductors and may be used with particular advantage in integrated circuit form. Use of the circuit as an impedance converter, current generator, voltage regulator and differential amplifier are illustrated.
Abstract:
A family of circuits characterized by storage mode operation in a switching circuit employs minority carrier injection from the base into the collector region of a semi-conductor device. The minority carrier charge stored in the collector thereafter causes amplified forward collector emitter current when forward collector potential is applied. Particular examples of the circuit family include inverters, single shot circuits, transistor oscillators and electronic switching in general.
Abstract:
A family of circuits characterized by storage mode operation in a switching circuit employs minority carrier injection from the base into the collector region of a semi-conductor device. The minority carrier charge stored in the collector thereafter causes amplified forward collector emitter current when forward collector potential is applied. Particular examples of the circuit family includes inverters, single shot circuits transistor oscillators and electronic switching in general.
Abstract:
A family of circuits characterized by storage mode operation in a switching circuit employs minority carrier injection from the base into the collector region of a semiconductor device. The minority carrier charge stored in the collector thereafter causes amplified forward collector-emitter current when forward collector potential is applied. Particular examples of the circuit family include inverters, single-shot circuits, transistor oscillators and electronic switching in general.
Abstract:
1,142,982. Automatic exchange systems. INTERNATIONAL BUSINESS MACHINES CORP. 10 Jan., 1968 [13 Jan., 1967], No. 1372/68. Heading H4K. In a ringing circuit for substations having a line transformer T with equal primary windings P2, P2, the ringing current is directed in parallel through the said windings so that no noise passes across the transformer to the switching equipment. To initiate ringing, a signal at terminal 42 is amplified to turn on a controlled rectifier D1 allowing current to flow from an A.C. source 12 to the ringing equipment 8 and thence to P1, P2. Transistor Q1 is turned on to bring the lower end of P1 to substantially ground potential. D5, D2 serve to discharge the ring capacitor during non-ringing periods. In the off-hook condition, the flow of D.C. turns on Q2 which turns off D1 to inhibit further ringing. At the same time an indication is given at terminal 41 through a dial integrator. The circuit is usefully employed in exchanges provided with solid state switching equipment.
Abstract:
1367058 Capacitive memory cells INTERNATIONAL BUSINESS MACHINES CORP 1 Feb 1973 [20 March 1972] 5028/73 Heading H3T A capacitor data storage cell CS is refreshed during a read operation by a latch circuit 9. Data is read from CS by a F.E.T. Q1 in response to a low voltage on the word line 4. If a high level (1) is stored, a transistor 7 conducts to raise the bit line 5, and this triggers the latch 9 which is an SCR in Fig. 1. The latch acts to raise the voltage on line 5 above that which was necessary to initiate triggering, and this raised voltage is fed through another transistor 6 to refresh the storage cell CS. The capacitance of the line 5 is discharged by a transistor 12 which is turned on at the beginning of a read operation, but turned off before the word line 4 voltage is lowered to effect reading. Transistors 12 and Q1 are turned on together, however, if it is desired to write a "0" (i.e. CS is earthed). To write a "1" a further transistor 13 is turned on to raise bit line 5 to +V while word line 4 turns on Q1. Instead of the SCR 9, an emitter coupled pair (16, 17, Fig. 2, not shown) with a positive feedback emitter follower 20, may be used; this has to be reset by a transistor inverter 25. The collector load in the emitter coupled pair may be either a resistor, or (Fig. 3, not shown) a F.E.T. (31) with a gate-source capacitor which is precharged by a further F.E.T. 29 and which boosts conduction of the load F.E.T. (31). The load F.E.T. (31) is fed with a pulsed power supply which is high during a read (refresh) operation, but goes low thereafter and resets the latch by way of the feedback transistor (30).
Abstract:
1,256,736. Transistor circuits. INTERNATIONAL BUSINESS MACHINES CORP. 12 March, 1969 [15 March, 1968], No. 12907/69. Heading H3T. [Also in Division G3] The collector of each transistor 10, 12, Fig. 2, of a complementary pair is connected to the base of the other transistor and is also connected to a respective diode 15, 17, to form a three terminal network 22, 23, 25 (or 21, 24, 25, Fig. 3, not shown). The diodes may be the functions of further transistors (Figs. 1b, 1c, not shown) and each transistor 10, 12 may be replaced by a complementary pair (Fig. 1a, not shown) in which the collector of one is joined to the emitter of the other, and the base of the one to the collector of the other. Circuits employing this three terminal network are: (a) An impedance converter (Fig. 4, not shown) in which a voltage is applied (at 25) and the impedance between a terminal (22) and ground is negative and proportional to the impedance Z R between another terminal (23) and ground; (b) A voltage regulator (Fig. 5, not shown) in which a voltage is applied (at 25), a reference voltage (at 23), a start-up diode (33) is connected in the reverse direction across diode (15) and a diode (37) is connected between the output terminals (22) and 23 for overvoltage protection, the voltage across a load R1 connected at 22 being regulated. In an alternative regulator (Fig. 8, not shown) two complete networks as in Fig. 2 are connected in cascade. If I 0 rises due to a fall in load impedance R1, then the positive feedback of the circuit further increases I 0 to keep V 0 unchanged; (c) A current generator (Fig. 6, not shown) in which the current through the common terminal (25) is regulated by a reference voltage applied (at 23) through an impedance R5, the terminal (22) being grounded; (d) A differential amplifier (Fig. 7, not shown) in which a voltage is applied through impedance Rb to one terminal (25) while the voltages to be compared are applied to another terminal (at 22) and through an impedance Z r (at 23), the output Vb appearing (at 25).
Abstract:
1,256,736. Transistor circuits. INTERNATIONAL BUSINESS MACHINES CORP. 12 March, 1969 [15 March, 1968], No. 12907/69. Heading H3T. [Also in Division G3] The collector of each transistor 10, 12, Fig. 2, of a complementary pair is connected to the base of the other transistor and is also connected to a respective diode 15, 17, to form a three terminal network 22, 23, 25 (or 21, 24, 25, Fig. 3, not shown). The diodes may be the functions of further transistors (Figs. 1b, 1c, not shown) and each transistor 10, 12 may be replaced by a complementary pair (Fig. 1a, not shown) in which the collector of one is joined to the emitter of the other, and the base of the one to the collector of the other. Circuits employing this three terminal network are: (a) An impedance converter (Fig. 4, not shown) in which a voltage is applied (at 25) and the impedance between a terminal (22) and ground is negative and proportional to the impedance Z R between another terminal (23) and ground; (b) A voltage regulator (Fig. 5, not shown) in which a voltage is applied (at 25), a reference voltage (at 23), a start-up diode (33) is connected in the reverse direction across diode (15) and a diode (37) is connected between the output terminals (22) and 23 for overvoltage protection, the voltage across a load R1 connected at 22 being regulated. In an alternative regulator (Fig. 8, not shown) two complete networks as in Fig. 2 are connected in cascade. If I 0 rises due to a fall in load impedance R1, then the positive feedback of the circuit further increases I 0 to keep V 0 unchanged; (c) A current generator (Fig. 6, not shown) in which the current through the common terminal (25) is regulated by a reference voltage applied (at 23) through an impedance R5, the terminal (22) being grounded; (d) A differential amplifier (Fig. 7, not shown) in which a voltage is applied through impedance Rb to one terminal (25) while the voltages to be compared are applied to another terminal (at 22) and through an impedance Z r (at 23), the output Vb appearing (at 25).
Abstract:
1367058 Capacitive memory cells INTERNATIONAL BUSINESS MACHINES CORP 1 Feb 1973 [20 March 1972] 5028/73 Heading H3T A capacitor data storage cell CS is refreshed during a read operation by a latch circuit 9. Data is read from CS by a F.E.T. Q1 in response to a low voltage on the word line 4. If a high level (1) is stored, a transistor 7 conducts to raise the bit line 5, and this triggers the latch 9 which is an SCR in Fig. 1. The latch acts to raise the voltage on line 5 above that which was necessary to initiate triggering, and this raised voltage is fed through another transistor 6 to refresh the storage cell CS. The capacitance of the line 5 is discharged by a transistor 12 which is turned on at the beginning of a read operation, but turned off before the word line 4 voltage is lowered to effect reading. Transistors 12 and Q1 are turned on together, however, if it is desired to write a "0" (i.e. CS is earthed). To write a "1" a further transistor 13 is turned on to raise bit line 5 to +V while word line 4 turns on Q1. Instead of the SCR 9, an emitter coupled pair (16, 17, Fig. 2, not shown) with a positive feedback emitter follower 20, may be used; this has to be reset by a transistor inverter 25. The collector load in the emitter coupled pair may be either a resistor, or (Fig. 3, not shown) a F.E.T. (31) with a gate-source capacitor which is precharged by a further F.E.T. 29 and which boosts conduction of the load F.E.T. (31). The load F.E.T. (31) is fed with a pulsed power supply which is high during a read (refresh) operation, but goes low thereafter and resets the latch by way of the feedback transistor (30).