RU2145462C1 - Digital-code controlled pulse generator - Google Patents

Abstract

FIELD: electrical and radio engineering; measuring, testing, process, and other industrial apparatuses. SUBSTANCE: pulse generator has digital-code register 1, synchronizing circuit 2, switching components 3, and set of transformers 4; current is supplied by switching component 3 from respective bit of digital-code register 1 to primary winding of each transformer; secondary windings of all transformers are phased out and connected to load. Transformation ratio is chosen for each transformer 4 according to weight of its controlling bit of register 1. Voltage pulse amplitude is stabilized across secondary winding of each transformer 4. Device generates voltage pulses of program-set amplitude corresponding to digital code which may be found useful for equipment determining material composition and property, polarizing piezoelectric materials, and miscellaneous purposes where preset-amplitude voltage pulses are required. EFFECT: enlarged functional capabilities. 3 dwg

Description

 The invention relates to a pulsed electrical and radio engineering and can be used to obtain a sequence of software defined by the amplitude of the pulses in the measuring, testing, technological and other industrial equipment.

 Generators of a similar purpose are known [1], [2]. Known pulse modulator [2], consisting of several transformers, in which the secondary windings and the load are interconnected in series.

 To ensure a change in the amplitude of the voltage pulses by a normalized value, a device is proposed in accordance with the digital code of the register, the functional diagram of which is shown in FIG. 1. The device includes a digital code register (1), a synchronization circuit (2), key elements (3) and a number of transformers (4). The state of each bit of the register of the digital code at the time specified by the synchronization circuit determines the supply to the primary winding of the corresponding current transformer depending on the code in the register.

 The circuit diagram of the synchronization is shown in FIG. 2. The digits of the register of the digital code set in the active state allow the pulses of the control device to pass into the key elements. In the synchronization circuit, AND-NOT logic elements are used, for example, on the K 561LA7 chip.

 Schematic diagram of the key element of one of the bits of the register of a digital code is shown in Fig.3. The schemes of the remaining key elements are similar.

 The pulse of the synchronization circuit is formed by the duration of the single-shot DD of FIG. 3. The pulse duration is set by an external RC circuit. The follower on the transistor VT2 transmit a pulse to the terminal transistor VT2. The current in the primary winding of the transformer is cut off by the transistor VT3, which operates in key mode.

 The transformer cores are made of ferrite NM 2000 ring shape with an inner diameter of 60 mm, rectangular cross section 20X15 mm. The primary windings of all transformers contain 10 turns of copper wire PEV - 2 with a diameter of 0.8 mm. Secondary windings are wound with a copper wire PEV - 2 with a diameter of 0.2 mm with the number of turns in accordance with the transformation coefficient of a particular transformer.

 The transformation coefficient of each transformer is chosen corresponding to the weight of the discharge of the register, which it is controlled.

 When the current is cut off in the primary winding of the transformer, the decreasing magnetic flux in the core induces a pulse in the secondary winding, the voltage amplitude of which is determined by the number of turns of the secondary winding. The pulse is limited in amplitude by the gas discharge stabilizer SG and fed through series-connected secondary windings of other transformers to the load. To protect against surges of current of opposite polarity, the secondary windings are connected by rectifier posts KTs106G. The secondary windings are phased to produce pulses of the same polarity.

 When the digital register is set to zero and the enable pulse of the synchronization circuit is applied to the key elements, there is no pulse on the secondary windings and the load.

 When the discharges of the digital register are set to active and the start pulse is supplied from the synchronization circuit to the key elements, the primary windings of all transformers will be energized and the generator will give a maximum amplitude pulse to the load.

 If part of the register bits is set to active, the key elements of the corresponding transformers are activated, the amplitudes of the voltage pulses induced in the secondary windings are added, and a voltage pulse with an amplitude is supplied to the load, depending on the value of the register code.

 The proposed device will allow you to receive voltage pulses with an amplitude corresponding to the digital code of the register, which can be used in equipment for determining the composition and properties of materials, for the polarization of piezoelectric materials and other applications where it is necessary to apply pulses with a given voltage amplitude.

Literature:
1. Mellekh E. M. Pulse modulator. Description of the invention 294240, 08.22.68, Cl. H 03 K 3/53.

 2. Gerasimov A. B. et al. High-voltage pulse generator. Description of the invention 454676 02.01.73, Cl. H 03 K 3/53.

Claims (1)

 A digitally controlled pulse generator comprising a digital code register and key elements of a corresponding digit of a digital code register, characterized in that a synchronization circuit is provided for supplying a trigger pulse, and a number of transformers, each of which is supplied with primary current by a key element of the corresponding discharge register of a digital code when a start pulse is applied, the secondary windings of all transformers are phased and connected in series with the load, the transformation coefficient and each transformer is selected corresponding to the discharge weight of the digital code register with which it is controlled, and the amplitude of the voltage pulse in the secondary winding of each of the transformers is limited by a stabilizer.

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