SU919087A1

SU919087A1 - Analogue switch

Info

Publication number: SU919087A1
Application number: SU802974988A
Authority: SU
Inventors: Александр Владимирович Ростовский; Игорь Владимирович Пугин
Original assignee: Предприятие П/Я А-7438
Priority date: 1980-09-03
Filing date: 1980-09-03
Publication date: 1982-04-07

Description

(54) АНАЛОГОВЫЙ КЛЮЧ(54) ANALOG KEY

1one

, Изобретение относитс к электронной технике, а более конкретно к электронной коммутационной технике, и может быть использовано, например, в системах многоканальной св зи дл кoм ryтa- .иии электронных сигналов.The invention relates to electronic engineering, and more specifically to electronic switching technology, and can be used, for example, in multichannel communication systems for which Ryta-ai and electronic signals.

Известен аналоговый ключ, содержащий два управл емых ключевых элемента, один из которых включен последовательно в цепь коммутируемого сигнала, а второй подключе} параллельно нагрузке, управл ющие электроды управл емых ключевых элементов соединены с шинами управле- . ни 1 .An analog switch is known that contains two controllable key elements, one of which is connected in series to the circuit of the switched signal, and the second is connected in parallel to the load, and the control electrodes of the controllable key elements are connected to the control buses. neither 1.

К недостаткам подобного устройства относитс низка точность передачи коммутируемого сигнала.The disadvantages of this device are the low transmission accuracy of the switched signal.

По технической сущности и схемной реализации наиболее близким к предла- . гаемому вл етс аналоговый ключ, содержащий три управл емых ключевых элемента, первый электрод первого управл емого ключевого элемента, второй электрол которого соединен с первымBy technical nature and circuit implementation closest to the predla-. A switch is an analog switch containing three controllable key elements, the first electrode of the first controlled key element, the second electrolysis of which is connected to the first

электродом второго управл емого ключевого элемента, подключен к входной шине, второй электрод второго управл емого ключевого элемента подключен к первой шине подключени нагрузки, управл ющие электрод управл емых к.лк чевых элементов соединены с пправлени 21 .the electrode of the second controlled key element is connected to the input bus, the second electrode of the second controlled key element is connected to the first bus connection of the load, the control electrode of the controllable electrical cells is connected to the direction 21.

К недостаткам известного устройства также следует отнести низкую точность The disadvantages of the known device should also include low accuracy

to передачи коммутируемого сигнала, котора обусловлена значительным уровнем ком гутационных помех, проникающих в цепь нагрузки из управл ющей цепи.To transfer a switched signal, which is caused by a significant level of switching noise penetrating the load circuit from the control circuit.

Цель изобретени повьпиение точts ности передачи коммутируемого сигнала.The purpose of the invention is the turning point of the accuracy of the transfer of the switched signal.

Поставленна цель достигаетс тем, что в аналоговый ключ, содержащий три управл емых ключевых элемента, первый электрод первого управл емого ключевого The goal is achieved by the fact that in an analog switch containing three controlled key elements, the first electrode of the first controlled key

Claims

20, the second electrode of which is connected to the first electrode of the second controlled key element, is connected to the input bus, the second electrode 39 of the second controlled key element is connected to the first bus connection of the load, the control electrodes of the controlled key elements are connected to control buses, a resistor is inserted, the combined second electrode of the first controlled key element and the first electrode of the second controlled key element are connected to the second bus connection of the load, the first electrode is rubbed of its controlled key element, the second electrode of which is connected through a resistor to the common bus and connected to the first bus connection of the load. The drawing is a schematic diagram illustrating an example of a specific implementation of the device. The analog switch contains the first 1 second 2 and third 3 controlled key elements, resistor 4. As controlled key elements, field effect transistors with pn junction are used. The source of transistor 1 (the first electrode of the first controlled key element) is connected to the input bus 5, C) the combined drains of transistors 1 and 2 (the combined second electrode of the first and the first electrode of the second controlled key elements) are connected to the second bus 6 connecting the load (Combined source of the transistor 2 and drain of the transistor 3 (combined in The second electrode and the first electrode of the third controlled key element are connected to the first load connection bus 7. The gates of the transistors (control electrode of the controlled key elements) are connected to the control buses 8 and 9. Field control elements can also be used as controlled key elements. transistors with a pn junction of various conductivities, field MOS transistors, combinations of these devices. The analog key functions as follows. The control bus lines 8 and 9 are supplied with control signals, switching the transistors 1 and 3 to the open state, and transistor 2 to the closed state. In this case, the analog switch is in the open state and the switched signal supplied to the bus 5 passes to the load. When the transistors 1 and 3 are locked and the transistor 2 is unlocked, the analog switch goes into the closed state. 7.4 Comm. Signal to the load is not received. The use of a serial-parallel switching circuit in an analog switch ensures the key-to-load ratio of the key resistance in the locked state to the key resistance in the open state. The advantage of the inventive shadow is to improve the accuracy of the transfer of the switched signal and is provided by reducing the level of switching noise penetrating the switched circuit from the control circuit. The proposed key scheme has full symmetry (the resistance of resistor 4 should be equal to the internal resistance of the source of the switching signal) and therefore, at any time, the levels of switching interference signals on the connection buses 6 and 7 are close in value and are compensated. Analog key containing three controlled key elements, the first electrode of the first controlled key element, the second electrode of which is connected to the first electrode of the second) Directional key element, is connected to the input bus, the second electrode of the second controlled key element is connected to the first bus connecting the load, the control electrodes of the controlled key elements are connected to the control buses, which is different from the fact that, in order to increase the accuracy of the transfer of the switched signal , a resistor is inserted into it, the combined second electrode of the first controlled key element and the first electrode of the second controlled key element are connected to the second bus connection of the load, the first electrode of the third controlled key element, the second electrode of which is connected to the common bus through a resistor, is connected to first load connection. Sources of information taken into account in the examination 1. US patent number 3636378, cl, 307 - 251, 1969. 2, SHEs on e. Seri 3 (Microelectronics). vyp..I500), 1978, p. 7, rice, 2 b.