摘要:
The present invention relates to fast complementary emitter follower drivers/buffers to be used in either a CMOS or pure complementary bipolar environment. The output driver (22) comprises top NPN and bottom PNP output transistors (T1, T2) with a common output node (N) connected therebetween. A terminal (15) is connected to the said output node (N) where the output signal (VOUT) is available. The pair of bipolar output transistors is biased between the first and second supply voltages (VH, GND). The output driver is provided with a voltage translator circuit (S) connected between the base nodes (B1, B2) of the output transistors (T1, T2). Logic signals (IN1, IN2), supplied by a preceding driving circuit (21), are applied to said base nodes. According to the invention, the voltage translator circuit (S) comprises two diodes (D1, D2) connected in series, preferably implemented with a main bipolar transistor having a junction shorted by a diode connected transistor to form a Darlington-like configuration. As a result, the voltage shift VS between the base nodes is selected to have the said output transistors operating at an operating point which ensures minimum delay and power consumption. In a typical bipolar technology, VS is made to be approximately equal to 1.5V. Additional features comprise the connection of a capacitor (C) between the base nodes and resistances (R1, R2) to the base nodes. The preceding driving circuit may be a CMOS logic gate or an ECL logic circuit.
摘要:
According to the present invention, a CMOS interface circuit (C2) similar to a latch made by two CMOS cross coupled inverters (INV1, INV2) is placed directly on the output node (14) of conventional BICMOS logic circuit (11) operating alone in a partial swing mode. This latch is made of four FETs P5, P6, N8, N9 cross-coupled in a conventional way with the feedback loop connected to said output node (14). The partial voltage swing (VBE to VH-VBE) naturally given by the output bipolar transistors (T1, T2) mounted in a push pull configuration is reinforced to full swing (GND to VH) by the latch at the end of each transition. The state of the output node if forced by the latch because of the high driving capability due to the presence of said output bipolar transistors (T1, T2). As a result, the improved BICMOS logic circuit (D2) has an output signal (S) that ranges within the desired full swing voltage at the output terminal (15). It is a characteristic of this embodiment that the structure of CMOS interface (C2) is always independent of the logic function implemented in the conventional BICMOS logic circuit (11). More generally, the CMOS interface circuit may have various physical implementations, however, it is always comprised of CMOS FETs and it becomes active at least in one of the GND to VBE or (VH-BE) to VH range.
摘要:
A multi emitter multi input BICMOS NAND circuit (30) is provided wherein an output node OUT connected to an output terminal (33) is coupled between pull up (31) and pull down (32) blocks. According to one embodiment of the present invention, the pull up block (32) is comprised of a plurality of identical basic cells, each comprised of a CMOS inverter (C31, C32) driving an NPN pull up transistor (T31, T32) mounted as an emitter follower. Logic signals (A31, A32) are applied on the inputs of the inverters (C31, C32), and the inverted signal (A31, A32) is available at the emitter of the emitter follower which corresponds to the output of the cell. All outputs are tied altogether to perform an OR function and are connected to said output terminal (33) to have a multi emitter like circuit. The pull down block (32) in this embodiment is comprised of 2 FETs (F31, F32) serially connected between said output node OUT and a discharge device such as a feedback NFET (Z) the gate of which is connected to said output node OUT. These 2 FETs are for driving a NPN pull down transistor (T), the collector of which is also connected to the output node OUT. The invention includes a number of other embodiments including a feedback inverter embodiment, a parasitic node discharge embodiment, and a BIFET latch embodiment.
摘要:
The invention provides novel implementations of a latch cell in CMOS gate array technology to produce latch dissymmetry and permit a single ended data input. The dissymmetry is produced by increasing the output impedance of the second stage of the latch cell, which can be done, either in a DC or in an AC mode, or even in a mixed version of both modes.
摘要:
In the transmitting chip, the bits are serialized and applied to a coding circuit in which bit stream (D) and its complement (D) are transformed into two signals (PH1 and PH2) under the control of a saw-tooth clock signal CK'. Signals (PH1 and PH2) are sent to the receiving chip, wherein they are applied to a decoding circuit which generates two signals (DJ) and (DK) representative of the data bits and a recovered clock signal CLK. The three signals (DJ, DK and CLK) as well as a frame signal (F) are used by a converting and demultiplexing circuit for assembling bytes of parallel data bits.
摘要:
A word line selection circuit includes a conventional Schottky diode decoder and a driver transistor which is connected to a word line. A word line is selected when the transistor is conductive and all associated diodes of the decoder are off. The base current of the driver transistor is defined by a control transistor whose conductivity is opposite to that of the driver transistor and which applies the selection current to the base of the driver transistor. A regulating transistor forms a current mirror with the control transistor to regulate the selection current. A compensation circuit associated with the regulating transistor modulates the collector current of the regulating transistor as a function of the driver transistor factor.
摘要:
A DTT type basic logic circuit exhibiting improved immunity to noise and including input diodes for receiving input signals A, B, . . .; an input transistor the emitter of which receives an additional input signal X and the base of which is connected to the anodes of the input diodes; and an output inverter transistor disposed so that the signal at the output thereof represents the logic function X(AB . . .). From this circuit, a family of logic circuits suitable for realizing very-large-scale-integration logic networks in a master slice can be developed. The master slice comprises general-purpose cells in which pre-diffused semiconductor elements can be interconnected to form the desired circuits.
摘要:
Duplicated circuit arrangement comprising a main processor (30) and its P bit data bus (44), and two identical redundant devices (21:22), each device is comprised of a processing element (23;35) performing the same task in parallel on a P bits word, and send/receive circuits (24,25;36,37) controlled by the main processor through lines (SR11 to SR22) to transmit said word to and from said main processor. For each device, the send/receive circuits are split into two parts. Send/receive circuit of the first device (21) is split in two parts (24, 25); the first part (24) handles the P/2 Most Significant Bits (MSB's) and the second part (25) handles the P/2 Less Significant Bits (LSB's). In normal operation, during the transmission step, only the first part (24) is allowed to send bits on one half (33) of the data bus (44). Symmetrically send/receive circuit of the second device (22), is also split in two parts (36, 37); the first section (36) handles the P/2 Most Significant bits (MSB's) and the second part (37) handles the P/2 Less Significant Bits Z(LSB's); only the second part (37) is allowed to send bits on the other half (34) of the data bus (44). Therefore, the data bus driving effort is equally shared between the two devices, the maximum number of simultaneous switching is P/2 for each device. This reduction allows greater transmission speed on large busses.
摘要:
A self-synchronising data bus analyser comprising a generator LFSR, a receiver LFSR and a comparator wherein the generator LFSR generates a first data set which is transmitted through a data bus to the comparator; and wherein the comparator compares the first data set with a second data set generated by the receiver LFSR and adjusts the receiver LFSR until the second data set is substantially the same as the first data set.
摘要:
A self-synchronising data bus analyser comprising a generator LFSR, a receiver LFSR and a comparator wherein the generator LFSR generates a first data set which is transmitted through a data bus to the comparator; and wherein the comparator compares the first data set with a second data set generated by the receiver LFSR and adjusts the receiver LFSR until the second data set is substantially the same as the first data set.