RU197320U1 - RADIO ELECTRONIC UNIT - Google Patents

Abstract

The utility model can be used in the manufacture of optoelectronic devices with a sufficiently high density of the layout of the internal space, and to ensure the correct operation of which it is necessary to ensure a high level of electromagnetic compatibility. The technical result is to increase the electromagnetic compatibility of the electronic unit while maintaining a tight layout of electronics and small overall dimensions. The radio-electronic unit contains a power and control board on which the power and control elements are located, and a system board with sensitive analogue radio elements located on it, output connectors made on the boards, inter-circuit connections, a mounting module, while the power and control elements are located on the outside power and control boards, sensitive analogue radio elements are located on the outside of the system board, board-to-board connections are made in the form of oncoming connectors on the boards, the mounting module is a mounting metal frame with holes for mounting elements located between the boards, while in the stack of layers of both boards are shielded layers that are connected to the mounting frame through metallized holes in the boards and between which are layers of sensitive analog and high-speed digital circuits, and in the stack of layers of each board there are blind transition metallized holes to ensure the transition of signals between the external and the nearest extreme internal nnimi signal layers and metallized vias hidden transition the transition for signals between opposed edge internal signal layers. 2 ill.

Description

The utility model relates to the field of development of designs of printed circuit boards and electronic blocks that can be used in optoelectronic devices for various purposes.

At present, optical-electronic devices (EIAs) are subject to high requirements for electromagnetic compatibility, reliability, weight and size characteristics and manufacturability. Therefore, there is a problem of increasing electromagnetic compatibility while maintaining or decreasing the weight and size characteristics of the EIA.

Known electronic unit (RF Patent No. 2 172 081, IPC H05K 1/00 (2000. 01), H05K 1/11 (2000. 01), H05K 1/14 (2000. 01), H05K 3/46 (2000. 01 ) published on 08/10/2001) containing a multilayer printed circuit board with the number of conductive layers N≥6, in which high-frequency and low-frequency connectors, as well as printed conductors, contact pads, and radio-electronic elements grouped by functional zones, are placed on the outer first and Nth conductive layers. Earth planes are located in the inner conductive layers adjacent to the outer conductive layers.

The disadvantage of the electronic unit is that the shielding layers inside the printed circuit board are designed to shield elements located in different functional areas on the board, and do not provide sufficient protection against external electromagnetic influences.

A radio electronic unit is also known (RF Patent No. 2366125, IPC H05K 1/00 (2006.01), H05K 1/18 (2006.01), H05K 9/00 (2006.01), H05K 3/40 (2006.01), H05K 3/46 (2006.01 ) published on 08.27.2009) which provides an increase in the efficiency of protecting the electronic block from electromagnetic interference and radio interference by using the spatial resources of printed circuit boards in it and manufacturing a screen protecting from electromagnetic interference by filling in a solder with a metallized groove connecting the shielding printed conductors and ground planes.

The disadvantages are the lack of integral connections between the boards and the case of the unit, as well as the difficulty of mounting the electronic unit, during which there is a high probability of violation of technological standards, which will lead to a decrease in the efficiency of protection of the electronic unit from electromagnetic interference.

The closest to the claimed technical solution for the technical nature and the technical result achieved is a radio-electronic unit (RF Patent No. 174943, IPC H05K 9/00 (2006.01), published on 11/14/2017), consisting of a housing with holes for external connectors made in it, the system board, the bottom cover, the power board, power modules, filter modules, the housing is divided into the power section and the system section. Common features are the separation of electronics according to their functional purpose into two separate boards: a power and control board on which the power and control elements are located and a motherboard on which sensitive analogue radio elements are located. Also, printed circuit boards have output connectors, circuit boards, components and fasteners, while the circuit boards are in electrical communication with the chassis (ground).

The main disadvantages of the prototype are the need to separate the electronic unit into isolated compartments, for the organization of a protective screen between the boards, as well as the need to use an external protective screen in the form of a metal casing from electromagnetic interference, which significantly affects the overall dimensions of the devices.

The technical task of the proposed utility model is to increase the electromagnetic compatibility of the electronic unit while maintaining a tight layout of electronics and small overall dimensions.

The technical result is achieved by the fact that in the electronic block containing the power and control board, on which the power and control elements are located, and the system board with sensitive analogue radio elements located on it, output connectors made on the boards, circuit boards, mounting module, according to this utility model, the power and control elements are located on the outside of the power and control board, sensitive analogue radio elements are located on the outside of the system plates, interboard connections are made in the form of counter connectors on the boards, the mounting module is a mounting metal frame with holes for mounting elements located between the boards, while in the stack of layers of both boards are shielded layers that are connected to the mounting frame through metallized holes in the boards and between which are layers of sensitive analog and high-speed digital circuits, and in the stack of layers of each board there are blind transition metallized holes for both baking the transition between the external signal and the nearest thereto extreme internal signal layers and metallized vias hidden transition the transition for signals between opposed edge internal signal layers.

The essence of the utility model, its feasibility and the possibility of industrial application are illustrated by the drawings presented in FIG. 1, 2 where:

FIG. 1 - electronic block;

FIG. 2 - stack of layers of printed circuit boards.

The numbers in FIG. 1, 2 the following positions are indicated:

1. electronic unit;

2. power and control board;

3. batteries and controls;

4. motherboard;

5. sensitive analog radioelements;

6. output connectors;

7. board connections;

8. metal frame;

9. holes on the metal frame;

10. fasteners;

11. metallized holes in the boards;

12. shielding layers;

13. dielectric layers;

14. blind transition metallized holes;

15. hidden transitional metallized holes;

16. layers of sensitive analog and high-speed digital circuits;

17. clearances between the printed conductors;

18. external signal layers;

19. The internal signal layers.

The electronic unit 1 (Fig. 1) contains a power and control board 2, on which the power and control elements 3 are located, and a system board 4 with sensitive analogue radio elements 5 located on it, as well as a mounting module made in the form of a metal frame 8 with holes 9 for fasteners 10, while the boards are equipped with output connectors 6, and board to board connections 7.

The power and control elements 3 are located on the front side of the power and control board 2, the sensitive analogue radio elements 5 are located on the front side of the system board 4, the interboard connections 7 are made in the form of oncoming connectors located on the rear side of the boards, the metal frame 8 of the mounting module is located between the rear the sides of the boards 2 and 4, while the power and control board 2 and the system board 4 are multi-layer, the stacks of layers of the multi-layer boards 2 and 4 contain external 18 and internal 16, 19 signal layers, die ctric 13 and shielding 12 layers, while the internal signal layers 16 of the sensitive analog and high-speed digital circuits are located between the shielding layers 12, the shielding layers 12 are in contact with the metal frame 8 through metallized through holes 11 made in the boards 2, 4 and the metal frame 8 . In the stacks of layers there are blind transition metallized holes 14 to ensure the transition of signals between the external 18 and the closest extreme internal 19 signal layers, as well as hidden transition metallized holes 15 for the transition of signals between the opposite extreme inner signal layers 19.

An example of a stack of layers of printed circuit boards is shown in FIG. 2, which in the particular case of execution in the number and structure of the stack of layers is the same for both printed circuit boards.

On the power and control board 2, tracing of the batteries and control circuits is performed on the external 18 and the closest extreme internal signal 19 layers of the board. The transition between the layers of these circuits is made using blind vias 14. On the next layer is an earth polygon that acts as a shielding layer 12. The stack of layers of the printed circuit board is made in the form of a symmetrical structure, so the number and purpose of the layers relative to the central dielectric layer 13 is the same. Between the two shielding layers 12 are layers 16 of sensitive analog and high-speed digital circuits. The shielding layers 12 are interconnected by hidden vias 15. The shielding layers 12 are also connected to the metallized fastening holes 11 through which they are connected to the metal frame 8 of the fastener module and the product body (not shown in FIG.) By means of fastening elements 10. Total printed a board may consist, for example, of N≥8 metallization layers, depending on the number of radio elements located on it and the number of electrical connections between them.

The structure of the stack layer of the motherboard 4 is performed in a similar manner. Sensitive analogue radio elements are located on the outer side 5 of the system board 4, and layers 16 of sensitive analog and high-speed digital circuits are located on the inner layers between the shielding layers 12 connected to the metallized holes 11 and the metal frame 8 by the fastening elements 10.

The operation of the device can be described as follows.

During operation, the power and control board 2 generates the voltages necessary for the functioning of the system board 4 and the components of the product for which the electronic unit 1 is designed. The process of generating power voltages is inevitably accompanied by electromagnetic interference. These electromagnetic interference do not affect the operation of the motherboard 4, because in the proposed technical solution, they are localized on the front side of the power and control board 2, due to which the sensitive radio elements 5 located on the front side of the system board 4 are protected from their effects. At the same time, the power and control board 2 and the system board 4 also have good protection against external electromagnetic interference, because Sensitive analog and high-speed digital circuits are located on the inner layers 16 of the printed circuit boards 2, 4 between the shielding layers 12, which are interconnected by blind vias 14 at all the boundaries of the shielding earth layers 12, which ensures a closed loop around the sensitive analog and high-speed digital circuits. The presence of blind vias 14 allows for the flow of power currents on the outer layers of the printed circuit boards without an end-to-end transition between the layers, which minimizes the number of gaps in the shielding layers 12, so that the electromagnetic fields arising at the borders of the gaps due to an increase in inductance do not affect sensitive analog and high speed digital circuits.

In the claimed solution, the electric and radio elements on the boards are grouped in such a way that the power and control elements are located on the front side of the power and control board, and the sensitive analog radio elements are located on the front side of the system board. This allows you to localize electromagnetic interference on the front side of the power and control board and not affect the correct operation of the system board, as well as increase the density of the electronics layout. Unlike the prototype, where the dividing wall between the boards plays the role of the screen, in the electronic unit there is no additional screen between the boards, and its function is performed by the ground shielding layers inside the stack of layers of the printed circuit boards, which protect sensitive analog and high-speed digital circuits from external electromagnetic influences. In the proposed technical solution, there are no through vias, the shielding layers are connected to the metallized holes of the printed circuit boards, which are installed on a metal frame and have electrical connection with the housing. This additionally allows you to get rid of the influence of external electromagnetic interference, which leads to increased electromagnetic compatibility of the claimed device as a whole. At the same time, the boards are made with the possibility of docking directly to each other using inter-board connections, and the fastening module is a metal frame with holes, which, together with the above advantages, can improve the overall dimensions of the electronic unit.

The proposed utility model is technically feasible and industrially feasible at the instrument-making enterprise, the tests carried out confirm the achievement of the claimed technical result.

Claims (1)

A radio electronic unit containing a power and control board on which the power and control elements are located, and a system board with sensitive analogue radio elements located on it, as well as a mounting module, the boards being provided with output connectors and circuit boards, characterized in that the elements power and control are located on the front side of the power and control board, sensitive analogue radio elements are located on the front side of the system board, board to board connections are made in In the opposite connectors, located on the back of the boards, the mounting module is a metal frame with holes for the mounting elements located between the back sides of the boards, while the power and control board and the system board are multilayer, the stacks of layers of multilayer boards contain external and internal signal layers , dielectric and shielding layers, while the internal signal layers of sensitive analog and high-speed digital circuits are located between the shielding layers, the contact t of shielding layers with a metal frame is carried out through through metallized holes made in the boards and the metal frame, in addition, there are blind transition metallized holes in the stacks of layers to ensure the transition of signals between the outer and the closest extreme internal signal layers, as well as hidden transition metallized openings for the transition of signals between the opposite extreme inner signal layers.

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