摘要:
A prediffused integrated circuit having rows of basic cells on a substrate. Each basic cell includes two MOS transistors connected in series through a common drain or source electrode, each transistor having a separate gate. All basic cells in a row are the same type while adjacent rows alternate between p-type and n-type.
摘要:
The invention relates to time-division exchanges in which the connection between the subscribers is established successively in time at the same frequency as a sampling of telephone signals. It consists in carrying out the spatial multiplex switching stage simultaneously on k words in series mode, each word using a separate spatial multiplex switch. A spatial multiplex switching stage with k independent elements is thus provided.This invention relates to time-division exchanges, in which the connection between the subscribers is established successively in time at the same rate as a sampling of telephone signals. The invention also relates to methods reshaping an exchange of this kind.These signals are generally sampled at a frequency of 8kc/s, after which the value of each sample is coded by a number of 8 bits. In most cases, this is followed by concentration which makes it possible, for example, to reduce the number of subscribers capable of being simultaneously connected from 256 to 32, the others awaiting a free connection. The degree of concentration is governed by the traffic expected on the subscriber lines which is known statistically. In general, the concentration circuit then delivers a frame of 32 channels multiplexed in time which is supported by a so-called multiplex junction circuit. It is also possible to carry out concentration with analogue samples, followed by encoding.The above mentioned numerical values are not critical, although they are generally used because of national and international standards.One significant problem is to guarantee adequate safety of operations in the event of failure of an element so that, instead of all the lines served by the automatic switching system having to be taken out of service, the blocking level is merely increased to a small extent.One solution to this problem is described in French Patent Application No. 75.05799. It comprises dividing shaping of an exchange of the type in question into n identical and independent sections connected at the level of the space-division switches by n busbars. Considering these spatial multiplex switches thus connected as a whole, it is apparent that they could be placed in the form of a matrix with n inputs and n outputs comprising n.sup.2 connection points.In the case of a high-capacity exchange this number of connection points would be too high. One known solution to this problem comprises using a multistage spatial multiplex switching network made up of a large number of matrices of small dimensions. Finally the number of connection points of these matrices as a whole is distinctly below n.sup.2, but it is no longer possible to return to the structure described above and the preceding protection system is no longer applicable.However, protection is essential, especially at the level of the spatial multiplex switch, because switching matrices are integrated in one and the same housing in which the failure of one element has consequential effects on all the others. Taking as an example a very simple integrated circuit comprising 4 multiplexers with 8 multiple inputs and used in the normal way in a connection network operating in parallel mode at a frequency of 2 MHz, this circuit will be used for more than 1000 calls. A failure of a circuit such as this is extremely serious.Various processes for replacing all or some of the safety elements of the switching network have already been proposed. These processes are attended by the disadvantage of requiring a large number of switches which, even if they are of the static type, may themselves be the origin of failures. In addition, the rescue switching procedure is complex and involves the loss of a large number of calls.In accordance with the present invention a time-division exchange is provided for switching binary words of k bits from a plurality of incoming parallel-mode PCM junctions to a plurality of output parallel-mode PCM junctions, said exchange comprising:first time-division switching means connected to said incoming PCM junctions for delivering said binary words in parallel mode;parallel-series conversion means for receiving said binary words from said first time-division switching means and delivering said binary words in series mode on k + n pluralities of input connections;matrix switching means connected to said k + n pluralities of input connections for delivering said binary words in series mode on k + n pluralities of output connections; said matrix switching means being divided into k + n independent distinct elements, each of said elements being connected respectively to one of said pluralities of input connections and to one of said pluralities of output connections and presenting to said binary words a plurality of paths between said input connections and said output connections;series-parallel conversion means connected to said k + n pluralities of output connections for delivering said binary words in parallel mode; andsecond time-division switching means connected to said series parallel conversion means for delivering said binary words to said plurality of output parallel-mode PCM junctions.
摘要:
A switching system for telephone exchanges employing pulse code modulation (PCM). The time division switching network uses standard circuits of a single type, i.e., symmetrical time division matrices (MTS) and, in a particular embodiment, one PCM telephone junction is multipled onto two inputs of two MTSs and the latter are rejoined by two bi-directional junctions so that the construction of telephone exchange according to the invention permits simple and easy extensions of the capacity of the switching system.
摘要:
The invention relates to switching matrices used in exchanges of time-division kind and to networks using that kind of matrices. It consists in utilizing at the input and output of a symmetrical time matrix, a multiplexer and a demultiplexer which enable the overall circuit to address an arbitrary IT (time slot) of an arbitrary incoming junction, to an arbitrary IT on an arbitrary outgoing junction. A network using only that kind of matrices is disclosed.
摘要:
A switching network with k=p+q inputs and as many outputs comprises one or more symmetrical time-division matrices, k being eight or a multiple of eight in the embodiments specifically disclosed. A larger number p of incoming subscriber links and a smaller number q of exchange outputs are respectively connected to p outgoing subscriber links and q exchange inputs. Digitized voice samples arriving over each incoming link in successive time slots of a recurrent frame, allocated to respective subscribers, are stored in each matrix and are selectively distributed to the reduced number of time slots sent to the exchange under the control of switching instructions from the exchange; conversely, signal samples received from the exchange in successive time slots are distributed to selected time slots of outgoing links. Signal paths can also be established between network inputs and outputs connected to incoming and outgoing links, thereby enabling direct communication between subscribers served by the network.
摘要翻译:具有k = p + q个输入和多个输出的交换网络包括一个或多个对称时分矩阵,在具体公开的实施例中,k为8或8的倍数。 较大数量的输入用户链路和较少数量的交换机输出分别连接到p个出站用户链路和q个交换输入。 分配给各个用户的经常性帧的连续时隙中的每个进入链路到达的数字化语音样本被存储在每个矩阵中,并且被选择性地分配给在交换指令的控制下发送到交换机的减少数量的时隙 交换; 相反,在连续时隙中从交换机接收的信号样本被分配到输出链路的选定时隙。 也可以在连接到输入和输出链路的网络输入和输出之间建立信号路径,从而实现由网络服务的用户之间的直接通信。
摘要:
The invention relates to the connection networks used for switching digital signals, more especially telephonic PCM signals. It consists in organizing the spatial stage of a network of the TST type operating in series mode so as to divide into two the number of switching planes of that network. Each plane is with blocking although the assembly is without blocking. Moreover the number of time paths that enables the spatial stage to be traversed is doubled.
摘要:
The modular switching network for time-division telephone exchanges, which may be applied to small-capacity time-division telephone exchanges, is constituted by the direct connection of pairs of subscriber and trunk line connecting units by PCM digital trunks, each connecting unit comprising a concentration-deconcentrator device for serving the subscribers associated with this connecting unit.
摘要:
The invention provides a method of synchronization of a junction in a pulse-code modulation (PCM) transmission network where any two multiplexing-demultiplexing stations equipped with independents clocks have to be brought into synchronism. For this purpose, the pulse trains (T.I.) of the PCM junction are alternatively recorded on two parallel channels A and B (registers RPA and RPB) and then memorized in a frame memory (MTR) by repeating the reading of the register when a risk of error is detected by comparison of the clocks. Means are provided for relocating the T.I. containing the multiframe locking code and the first frame of multiframe.
摘要:
This invention relates to a device for organizing access to a bus connecting a memory to at least two entities asynchronous binary signals representing requests for access to the bus. The device supplies binary signals to authorize the access to an entity based on a priority determination between the different requests and includes a priority decoder in wired logic associated with an input register. A loading of the state of the access request signals happens, if an access request is present while a read or write cycle of the memory is executed, upon the arrival of a pulse on a signal issued by a memory controller associated with the memory and indicative of the end of a memory cycle.
摘要:
This invention relates to an integrated HDLC circuit of the type including at least one HDLC controller and one DMA controller, and means for organizing the access to a first external bus for connection to an external memory, via an internal bus to which are connected different entities, which require to have access to the external memory, the internal bus being connected to the first external bus via a memory controller integrated in the HDLC circuit.