CN204929407U

CN204929407U - Pad formula short circuit resistance

Info

Publication number: CN204929407U
Application number: CN201520592835.0U
Authority: CN
Inventors: 付辉辉
Original assignee: Chongqing Blue Bank Communication Technology Co Ltd
Current assignee: Chongqing Lanan Technology Co ltd
Priority date: 2015-08-07
Filing date: 2015-08-07
Publication date: 2015-12-30
Anticipated expiration: 2025-08-07

Abstract

The utility model discloses a pad formula short circuit resistance, its key lies in: electric conductor including two relative pads and connection conduct short circuit resistance between two pads, the pad with the electric conductor all loses through the copper foil acid on the printed circuit board and forms. For suppression circuit noise, improved circuit stability needs, the width of electric conductor is 0.3-0.4mm, and length is 0.3-0.4mm, the width of pad is 0.4-0.6mm, and length is 0.4-0.6mm, the fillet radius of pad is 0.1mm-0.2mm. Beneficial effect: (1 )Save 0 ohmic resistance's cost and simple structure, effectively divide different lattice networks, play 0 ohmic resistance and use function and effect in the circuit, (2 )Increase the pad area, improved circuit's stability, (3 )Need not punch and remove the welded trouble from the circuit board when using pad formula short circuit resistance.

Description

Pad formula short-circuit resistance

Technical field

The utility model belongs to for the short-circuit resistance in pcb board circuit, specifically, is a kind of pad formula short-circuit resistance.

Background technology

In most of integrated circuit, for debugging the reasons such as convenient or compatible design, in pcb board circuit, usually using 0 Ohmic resistance by current delivery to next lattice network, do the circuit region being convenient to divide difference in functionality like this, and current value being constant.

0 traditional Ohmic resistance mainly comprises pin resistance and Chip-R two type, and pin resistance needs on PCB, arrange corresponding welding hole and pad, increases workload; Use during Chip-R and do not need to punch on pcb board, but pin is less, extremely inconvenient during human weld; Moreover, manufacture 0 ohm of pin resistance or 0 ohm chip resistor all need certain cost; And 0 ohm of pin resistance or 0 ohm chip resistor are actually the less resistance of resistance, and and non-zero ohm, a certain amount of loss can be caused in side circuit.

Utility model content

In view of this, the utility model provides a kind of pad formula short-circuit resistance, and pad and the electric conductor be connected between pad of this pad formula short-circuit resistance are formed by the Copper Foil acid etching on printed circuit board, does not therefore need to weld 0 extra Ohmic resistance.

Concrete technical scheme is as follows:

A kind of pad formula short-circuit resistance, its key is: the electric conductor comprising two relative pads and be connected to as short-circuit resistance between two pads, described pad and described electric conductor are all formed by the Copper Foil acid etching on printed circuit board (PCB).

Based on the pad formula short-circuit resistance of said structure, during PCB drawing, directly call packaged pad formula short-circuit resistance and connect in circuit, do not need to draw pad again; After printed circuit board corrosion, do not need to weld 0 extra Ohmic resistance yet, save the cost of 0 Ohmic resistance, and remove the trouble of welding from.

Further, the width of described electric conductor is 0.3 ~ 0.4mm, and length is 0.3 ~ 0.4mm; The width of described pad is 0.4 ~ 0.6mm, and length is 0.4 ~ 0.6mm, and the radius of corner of described pad is 0.1mm ~ 0.2mm.During PCB drawing, be generally and suppress noise to need the live width of holding wire to be set to: 0.2 ~ 0.3mm, therefore the conductor width of pad formula short-circuit resistance is designed to the width slightly larger than holding wire, obviously can divide the lattice network of difference in functionality in circuit, play 0 Ohmic resistance application function in circuit and effect; In addition, the relational expression of the copper-clad surface sum electric current of PCB design is I=K × T ^0.44× S ^0.75, wherein I is the maximum current of allowing, unit is ampere; K is correction factor, generally covers copper cash and gets 0.024 when internal layer, get 0.048 when skin; T is maximum temperature rise, and unit is degree Celsius; S is for covering copper area, and unit is mil; According to this relational expression, it is larger that S covers copper area, also strain is large mutually to allow the lowest high-current value I passed through in unit interval, therefore, according to PCB drafting standard, the conductor width of pad formula short-circuit resistance is designed to the width slightly larger than holding wire, what increase pad formula short-circuit resistance covers copper area, improve pad formula short-circuit resistance in the unit interval and allow the lowest high-current value passed through, increase the stability of circuit.

Beneficial effect: (1) saves the cost of 0 Ohmic resistance and structure is simple, effectively divides heterogeneous networks circuit, plays 0 Ohmic resistance application function in circuit and effect; (2) strengthen bonding pad area, improve the stability of circuit; (3) use during pad formula short-circuit resistance and do not need punch to circuit board and remove the trouble of welding from.

Accompanying drawing explanation

Fig. 1 is structure chart of the present utility model;

Fig. 2 is fundamental diagram of the present utility model.

Embodiment

Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail.

A kind of pad formula short-circuit resistance as shown in Figure 1, its key is: the electric conductor comprising two relative pads and be connected to as short-circuit resistance between two pads, described pad and described electric conductor are all formed by the Copper Foil acid etching on printed circuit board (PCB).

It can also be seen that from Fig. 1, in a particular embodiment, the width of described electric conductor is 0.3048mm, and length is 0.3810mm; Described pad is square, and width and length are all 0.5080mm, and for preventing point discharge, right angle is arranged to the fillet that radius is 0.1016mm; In like manner, also pad can be arranged to the circle of diameter slightly larger than conductor width.During PCB drawing, be generally and suppress noise to need the live width of holding wire to be set to: 0.2 ~ 0.3mm, therefore the conductor width of pad formula short-circuit resistance is designed to the width slightly larger than holding wire, obviously can divide the lattice network of difference in functionality in circuit, play 0 Ohmic resistance application function in circuit and effect; In addition, the relational expression of the copper-clad surface sum electric current of PCB design is I=K × T ^0.44× S ^0.75, wherein I is the maximum current of allowing, unit is ampere; K is correction factor, generally covers copper cash and gets 0.024 when internal layer, get 0.048 when skin; T is maximum temperature rise, and unit is degree Celsius; S is for covering copper area, and unit is mil; According to this relational expression, pad formula short-circuit resistance to cover copper area S larger, also strain is large mutually to allow the lowest high-current value I passed through in the unit interval.Therefore, according to PCB drafting standard, the conductor width of pad formula short-circuit resistance is designed to the width slightly larger than holding wire, what increase pad formula short-circuit resistance covers copper area, improve pad formula short-circuit resistance in the unit interval and allow the lowest high-current value passed through, increase the stability of circuit.

Operation principle of the present utility model as shown in Figure 2, pad formula short-circuit resistance is in use for distinguishing the lattice network of difference in functionality, the circuit voltage name that pad formula short-circuit resistance left end connects is called+VSYS, the circuit voltage name that right-hand member connects is called+VSYS_BKLTIN, the current value flowing through pad formula short-circuit resistance is constant, the magnitude of voltage V at its two ends ₁and V ₂equal.

The foregoing is only preferred embodiment of the present utility model; not in order to limit the utility model; all do within spirit of the present utility model and principle any amendment, equivalent to replace and improvement etc., all should be included within protection range of the present utility model.

Claims

1. a pad formula short-circuit resistance, is characterized in that: the electric conductor comprising two relative pads and be connected to as short-circuit resistance between two pads, described pad and described electric conductor are all formed by the Copper Foil acid etching on printed circuit board (PCB).

2. pad formula short-circuit resistance according to claim 1, is characterized in that, the width of described electric conductor is 0.3 ~ 0.4mm, and length is 0.3 ~ 0.4mm; The width of described pad is 0.4 ~ 0.6mm, and length is 0.4 ~ 0.6mm, and the radius of corner of described pad is 0.1mm ~ 0.2mm.