GB847114A - Improvements in or relating to data processing circuits - Google Patents

Abstract

847,114. Controlled non-linear inductors. SOC. D'ELECTRONIQUE ET D'AUTOMATISME. April 30, 1957 [May 3, 1956; Sept. 8, 1956], No. 13772/57. Class 40 (9). In a data processing circuit which performs logical operations on binary information represented by the presence or absence of D.C. signals, a transformer 4, Fig. 1, having a core with a rectangular hysteresis characteristic is connected to an A.C. source 3 over one or more branch circuits 1-2, 1<SP>1</SP>-2<SP>1</SP>, each comprising A.C. windings 10, 11 of magnetic cores 14, 15, the magnetisation levels of which are individually determined by D.C. signals in the respective control windings 12, 13, each magnetic core 14, 15 having a saturation current value which is low relative to that of the transformer so that all the cores in a branch circuit must be saturated by their respective control signals for the current from the A.C. source to be of sufficient value to change the remanent state of the transformer core and thereby establish an output in its secondary winding 6. Each branch circuit thus carries out the logical AND operation while the parallel branch circuits form a further logical OR network since full conduction in any branch brings the transformer into an operative condition. The transformer secondary winding may be centre-tapped, as shown in Fig. 2, and associated with rectifiers 16 to provide a full-wave rectified output which is smoothed by a condenser 17, the resultant signal controlling a magnetic core 20 which may be connected in one of the branch circuits such as 1-2. Alternatively the alternating transformer secondary current may directly control a magnetic amplifier 24, Fig. 3, the output of which is derived from an A.C. source 25 and rectified at 26. In a modification, Fig. 4, a complementary output is obtained by including an anti-phase A.C. source 28 in the amplifier control circuit. It is stated that the data processing arrangement forms a logical AND unit if a single branch circuit 1-2 is provided, or a logical OR unit if each of a number of branch circuits comprise but a single core. The output circuit of the transformer may be modified as shown in Fig. 7 by connecting the secondary winding 6 in series with an A.C. source 43 and a rectifier 44. In this case operation is similar to that of a resetting type magnetic amplifier. With small branch currents no flux excursion takes place in the transformer, and a high output current passes through the secondary winding during alternate half-cycles of the A.C. source 43. If, however, all the cores in a branch 1-2 are saturated by control signals, then current in the transformer primary winding 5 is sufficient to cause a reduction of the core flux and so reduce the secondary winding current in the following half-cycle. This output is complementary and in the arrangement shown is applied to three control windings 46, 47, 48 simultaneously.