CN213484750U

CN213484750U - Filter circuit and module

Info

Publication number: CN213484750U
Application number: CN202022901551.9U
Authority: CN
Inventors: 谭长顺
Original assignee: Chongqing Simcom Wireless Solutions Co ltd
Current assignee: Chongqing Simcom Wireless Solutions Co ltd
Priority date: 2020-12-03
Filing date: 2020-12-03
Publication date: 2021-06-18
Anticipated expiration: 2030-12-03

Abstract

The utility model discloses a filter circuit and module, wherein filter circuit for the filtering of the power supply pin of chip, the chip includes at least two the power supply pin, filter circuit includes filter capacitor, all there are two to the target power supply pin, one in the power supply pin filter capacitor sets up from two position department in the within range of the predetermined distance of target power supply pin, filter capacitor's one end respectively with two target power supply pin and power output end electricity are connected, filter capacitor's other end ground connection. The number of the filter capacitors can be effectively reduced through the arrangement of the filter circuit, the hardware cost is reduced while the corresponding filter function is realized, the layout area of devices is further reduced, the packaging size of the module is reduced, and the integration of the module is facilitated.

Description

Filter circuit and module

Technical Field

The utility model relates to a hardware circuit design technical field, in particular to filter circuit and module.

Background

With the development of electronic technology, the requirements for high integration of modules and stability of systems are also higher and higher. In order to ensure the stability of the system circuit, a filter circuit is often added between a PMU (Power Management Unit) and a CPU (Central Processing Unit), and the current filter circuit is to add one or more capacitors at each Power supply pin of the CPU, which causes the excessive filter capacitors in the circuit and the required layout area of the device to be increased, thereby causing the excessive size of the module to be large.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is that the filter capacitance quantity of the filter circuit in order to overcome each power supply pin of prior art module is too much, leads to the too big defect of module size, provides a filter circuit and module.

The utility model discloses an above-mentioned technical problem is solved through following technical scheme:

the utility model provides a filter circuit for the filtering of the power supply pin of chip, the chip includes at least two the power supply pin, filter circuit includes filter capacitor, all there are two in the power supply pin to be the target power supply pin, one filter capacitor sets up and is being kept away from two position department in the scope of the predetermined distance of target power supply pin, filter capacitor's one end respectively with two target power supply pin and power output end electricity are connected, filter capacitor's other end ground connection.

Preferably, the power output terminal is an output terminal of the power management unit.

Preferably, the preset distance is less than 3mm (millimeters).

Preferably, the distance between two of the target power supply pins is smaller than the distance between each of the target power supply pins and the other power supply pins.

Preferably, the filter capacitor and a PCB (Printed Circuit Board) trace of the target power supply pin are in a star shape.

The utility model also provides a module, the module includes as above filter circuit.

The utility model discloses an actively advance the effect and lie in: through setting up a filter capacitor in the position department of two target power supply pin within a predetermined distance, filter capacitor's one end is connected with two target power supply pins and power output end electricity respectively, filter capacitor's the other end ground connection's the mode of setting up, two power supply pins supply a filter capacitor promptly, can effectively reduce filter capacitor's quantity, the hardware cost has been reduced when realizing corresponding filtering function, still further reduced device layout area and then make the encapsulation size of module reduce, be favorable to integrating of module.

Drawings

Fig. 1 is a schematic structural diagram of a filter circuit according to embodiment 1 of the present invention.

Fig. 2 is another schematic structural diagram of the filter circuit according to embodiment 1 of the present invention.

Fig. 3 is a schematic diagram of a local layout of the filter circuit on the PCB according to embodiment 1 of the present invention.

Fig. 4 is a schematic structural diagram of a module according to embodiment 2 of the present invention.

Detailed Description

The present invention is further illustrated by way of the following examples, which are not intended to limit the scope of the invention.

Example 1

This embodiment provides a filter circuit, as shown in fig. 1 for the filtering of the power supply pin of chip 1, chip 1 includes at least two power supply pin VCC1 and VCC2, filter circuit package filter capacitor C1, all there are two in the power supply pin for target power supply pin VCC1 and VCC2, during the PCB overall arrangement, one filter capacitor C1 sets up and is leaving two the position department in the scope of target power supply pin VCC1 and VCC2 preset distance, filter capacitor C1's one end respectively with two target power supply pin VCC1 and VCC2 and power output end 2 electricity are connected, filter capacitor C1's other end ground connection.

In this embodiment, the power output terminal 2 is an output terminal of a power management unit.

Specifically, the preset distance in this embodiment is less than 3mm, and a distance between two target power supply pins is less than a distance between each target power supply pin and another power supply pin. Specifically, as shown in fig. 2, in this embodiment, chip 1 has 4 the target power supply pin is VCC1, VCC2, VCC3 and VCC4 respectively, in the filter circuit the quantity of filter capacitor is 2, is C1 and C2 respectively, and wherein the distance between target power supply pin VCC1 and target power supply pin VCC2 is less than the distance between target power supply pin VCC1 and target power supply pin VCC3 and the distance between target power supply pin VCC1 and target power supply pin VCC4, and therefore, target power supply pin VCC1 and target power supply pin VCC2 share one filter capacitor C1, and similarly, target power supply pin VCC3 and target power supply pin VCC4 share one filter capacitor C2.

In this embodiment, the filter capacitor and the PCB trace of the target power supply pin are in a star shape, and the two target power supply pins sharing one filter capacitor have reduced mutual influence through the star-shaped trace.

In an optional implementation manner, the filter circuit further includes a voltage stabilizing capacitor C3, one end of the voltage stabilizing capacitor C3 is connected to the output terminal of the power management unit 2, one end of the voltage stabilizing capacitor C3 is further connected to one end of the filter capacitor C1, and the other end of the voltage stabilizing capacitor C3 is grounded. Through set up voltage stabilizing capacitor in filter circuit, further guaranteed filter circuit's stability, avoid causing the circuit unusual damage even because of voltage fluctuation.

To further illustrate the technical solution and technical effects of the present embodiment, as shown in fig. 3 by way of specific example, a CPU1 and a PMU2 are disposed on a PCB baseboard 4, a CPU1 has corresponding power supply pins VCC31, VCC32, VCC33, and VCC34, a PMU2 has a power output terminal VCC35, in this embodiment, a specific model of a CPU1 is SDX55, a specific model of a PMU2 is PMX55, when a VCC power supply path layout is performed, a power supply trace is led out from the power output terminal of the PMX55 and connected to one end of a voltage stabilizing capacitor 53, and then connected to one end of a filter capacitor 51 of the SDX55 and one end of the filter capacitor 52 after passing through one end of the voltage stabilizing capacitor 53, wherein VCC31 is closest to VCC32, VCC33 is closest to VCC34, so that the power supply trace of VCC31 and the VCC32 is connected to one end of the filter capacitor 51, 33 and the VCC33 is connected to one end of the filter capacitor VCC 52, and the other end of the filter capacitor 53 is a ground, the ground terminal 53 is connected to the ground, the other end of the filter capacitor 51 is a ground terminal 61, the other end of the filter capacitor 52 is a ground terminal 62, and the ground terminal 61 and the ground terminal 62 need to be directly drilled to the main ground layer of the PCB to be connected to the main ground layer. It can be seen from the above layout scheme that, compared with the existing layout scheme, 2 filter capacitors can be saved in the VCC power supply path, and the SDX55 has multiple paths of similar power supply paths, and the filter capacitors for each path of power supply are arranged according to the above layout scheme, so that the number of the filter capacitors can be effectively reduced, the hardware cost is reduced while the corresponding filtering function is realized, and the device layout area is further reduced, thereby reducing the packaging size of the module.

In this embodiment, through setting up a filter capacitor in two target power supply pin position departments in the predetermined distance, filter capacitor's one end is connected with two target power supply pins and power output end electricity respectively, filter capacitor's the other end ground connection's the mode that sets up, can effectively reduce filter capacitor's quantity, reduced the hardware cost when realizing corresponding filtering function, still further reduced device layout area and then made the encapsulation size of module reduce, be favorable to integrating of module.

Example 2

This embodiment provides a module, as shown in fig. 4, where the module 3 includes the filter circuit in embodiment 1.

Compared with the existing module, the module provided in the embodiment has the advantages that the number of filter capacitors is reduced while the corresponding filtering function is realized, the hardware cost is reduced, the layout area of devices is further reduced, the packaging size of the module is reduced, and the integration of the module is facilitated.

Although specific embodiments of the present invention have been described above, it will be understood by those skilled in the art that this is by way of example only and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and the principles of the present invention, and these changes and modifications are all within the scope of the present invention.

Claims

1. The filter circuit is used for filtering power supply pins of a chip, the chip comprises at least two power supply pins, and the filter circuit comprises a filter capacitor.

2. The filter circuit of claim 1, wherein the power supply output is an output of a power management unit.

3. The filter circuit of claim 1, wherein the predetermined distance is less than 3 mm.

4. The filter circuit of claim 3, wherein a distance between two of the target supply pins is less than a distance between each of the target supply pins and the other supply pins.

5. The filter circuit of claim 4, wherein the filter capacitance and the PCB trace of the target supply pin are in a star formation.

6. A module, characterized in that the module comprises a filter circuit according to any one of claims 1-5.