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PCB Prototype Image:Integrity of power in PCB circuit

Integrity of power in PCB circuit

Power integrity and signal integrity are closely related to each other. Under many circumstances, the main cause for distortion of signal is from power system. For example, rebounding noise from the ground is too large; the design of decoupling capacitance is not appropriate; returning impact is serious; division of multi-power or multi-surface is not good; unreasonable design of the floor; uneven current distribution, etc.. 1)、Power distribution systemPower integrity is very complicated and the key lies in how to control the resistance between the power systems (between the power and the surf...

January 13, 2020

PCB Prototype Image:The method and steps of shoveling PCB

The method and steps of shoveling PCB

Firstly, after getting the PCB, you should record the model No., parameters, position of all the components on it, especially the direction of diode and triode, as well as the direction of IC gap. It is advisable to take some pictures of the position of the electronic components by digital camera. Secondly, both all components should be removed and the tin hidden inside the PAD holes should be removed. Besides, PCB Prototype should be cleaned with ethyl alcohol and put inside the scanister. When scanning with scanisters, pixel should be enhanced in order to get a clear image and start POHTOSH...

January 6, 2020

PCB Prototype Image:PCB processing technology and equipment

PCB processing technology and equipment

PCB equipment includes plating wires, electroless plating copper, DES wires, DES wires, cleaning machines, OSP lines, electroless nickel gold wires, press machines, exposure machines, roasting machines, AOI, twist bump-cutter machine, edging machines, materials providing machines, vacuum packaging machines, hammering machines, drilling machines, vacuum pressing machines, tin spraying machines, CMI series, light drawing machines, etc.. Circuit board can be divided into single-layer board, multi-layer board and multi-layer printing board. The basic production process of single-layer boards are a...

December 30, 2019

PCB Prototype Image:Processing technique of SMD

Processing technique of SMD

1. Based on Gerber and BOM from the client, technology files are prepared to generate coordinate files. 2. Be sure to check whether all production materials are prepared well and whether the production sheets are ready. Besides, PMC production plan should also be confirmed. 3. After programming SMT, be sure to check the stem board to make sure they are all right.4. Production of steel mesh should be based on SMT technique. 5. Tin cream should be applied to ensure tin cream is even and consistent with proper thickness. 6. Electronic components are stuck to the circuit board through SMT machines...

December 23, 2019

PCB Prototype Image:PCBA test

PCBA test

PCBA test is the most crucial quality control step in the entire PCBA processing procedure, which should be in strict compliance with PCBA test standard. Testing dots on the circuit boards should be tested based on the test plan provided by the client. There are 5 kinds of PBCA tests in general: ICT, FCT, burn in test, fatigue test and severe conditions test. ICT (In Circuit Test) mainly includes tests for on-off of circuits, voltage and current value, and the fluctuating curves, amplitude, noise, and so on. FCT (Functional Circuit Test) needs to be conducted via IC program, which aims to cond...

December 16, 2019

PCB Prototype Image:Several important elements in the later check of PCB design

Several important elements in the later check of PCB design

When the routing in finished on one PCB Prototyping board and there is no error in both the connecting and the distance, does it mean that this piece of PCB board is finished. Of course, it is not true. Many beginners, including some experienced engineers, tend to be rash in the process and ignore the follow-up checking due to urgency in time, impatience or overconfidence. As a result, some basic bugs occur, for example, wires are not wide enough; silk screen of the component marks is printed on the holes; the socket is too near; loop occurs in the signal, and so on., which may lead to electr...

December 9, 2019

PCB Prototype Image:Why does poor tin welding always occur in PCB

Why does poor tin welding always occur in PCB

In the process of PCB Prototype design and production, do you usually meet the problems that poor tin welding always occur in PCB? For engineers, once poor tin welding always occur in one PCB, it means re-welding or re-production is needed, so the effect is rather painful. So, what are the major reasons for poor tin welding in PCB? How can we avoid this problem?Generally, the reason for poor tin welding in PCB is that some parts of the PCB surface is not coated with tin, so there are many PCBs with poor tin welding. There are many reasons for poor tin welding in the PCB, which can be conclude...

December 2, 2019

PCB Prototype Image:Maintenance of PCB dividing board

Maintenance of PCB dividing board

1.The reasons for the operational problems occurring to PCB Prototyping dividing boards: When the storage battery has not enough power, connection between the storage battery and the staring motor will be disconnected. Oxidation occurs to the storage battery or wiring cards. There is poor contact between the electromagnetic switch and the two binding posts, or the flow deflector is seriously eroded for burning; there is abrasion or break in the electric brush, or the electric brush is stuck in its frame; there is oil dirt in the current rectifier of the electric brush or the current rectifie...

November 25, 2019

PCB Prototype Image:The common malfunctions and the treatments of PCB sub-machine

The common malfunctions and the treatments of PCB sub-machine

1.If the indicator light is off when the switch in opened: one possible reason is the fuse wire is fused and needs to be replaced; the other possible reason is the emergency switch is off. 2.Wrong miles counting: one possible reason is that the miles counter is broken and needs to be replaced; the other possible reason is that there is too much dust on the mile counter and it only needs cleaning. 3.Knife hitting the left side board: one possible reason is that light sensation on the left side is broken and needs to be replaced; the other possible reason is that there is too much dust on mile c...

November 5, 2019

PCB Prototype Image:An analysis on the design method and main points of PCB chart

An analysis on the design method and main points of PCB chart

In PCB design, the following points need to be paid special attention:1.Routing direction: Seen from the welding surface, components’ arrangement should be in line with the schematic graph as much as possible and the routing should be best line with that of the routing graph, because the welding surface often needs all kinds of parameter testing in the production process. This will be helpful to the inspection, adjusting and maintenance in the manufacturing process(Remark: It must be on condition that all the requirements in terms of performance, machine assembling, board laying out, should be...

October 30, 2019

PCB Prototype Image:Five major trends in terms of PCB technology development

Five major trends in terms of PCB technology development

More and more electronic equipments are going high-performance, high-speed, light and thin. As a multi-discipline industry, PCB technology plays a key role in high-end electronic equipment. Be it rigid, flexible or multi-layer boards with the combination of rigidity and flexibility, or module substrate with IC enclosing substrate, PCBs have made huge contributions to high-end electronic equipment. PCB field plays a crucial role in the electronic connecting technology. Mankind has entered a highly informational society in the 21st century and PCB inevitably serves an important pillar in the inf...

October 22, 2019

PCB Prototype Image:The design principle of single chip control board in PCB design

The design principle of single chip control board in PCB design

1.Layout of electronic components When laying out electronic components, relevant components should be put close to each other, such as, clock generator, crystal oscillator, input end of CPU clock, which easily generate noise, so they should be placed closer to each other. For components which easily produce noise, small current circuits, large current circuits, switching circuit, etc., they should be away from the logic control circuit with single chip as well as ROM and RAM. If possible, these circuits can be made into circuit boards, which will be beneficial to resisting interference and im...

October 16, 2019

PCB Prototype Image:Reservation and validity period of PCB

Reservation and validity period of PCB

After passing the finished goods inspection, PCB will be packed with vacuum package to be shipped. Why does PCB need vacuum packaging? How to reserve PCB after vacuum package? How long is the validity period? PCB factories will make a brief introduction of the reservation method and validity period of PCB. Why does PCB needs vacuum packaging? This is a small question but deserves significant consideration from PCB manufacturers. Once the PCB is not enclosed well, the immersion gold on the surface, spraying tin and welding parts will be oxidized and affect welding, which will be harmful to pro...

October 8, 2019

PCB Prototype Image:Differences between the positive layer and negative layer on the PCB

Differences between the positive layer and negative layer on the PCB

Negative layer on the PCB: Generally, we mean tenting processing, in which acid chemical liquid is used for etching negative side, because the circuit or copper side should be transparent after the base film is produced. The part which is removed is black. After the circuit production process is exposed, the transparent part will be hardened as dry film photoresist has chemical action under illumination. Next, dry films without hardening will be removed in the developing process. Then it comes to the lead tin plating process, in which tin and lead are plated on the copper side whose dry film i...

September 24, 2019

PCB Prototype Image:How to reduce mistakes in PCB design and improve efficiency?

How to reduce mistakes in PCB design and improve efficiency?

Circuit board design is a key and time-consuming task. Whenever problems arise, engineers need to inspect the components one by one via network. That is to say, the attention and circumspection it requires is no less than the chip design. A typical circuit board design is usually composed of the following steps:The time it takes in the first three steps is the longest because schematic diagram inspection is a long manual process. Imagine a SoC circuit board which is connected with 1000 or 1000 more lines. Manual inspection of every single line is a long and boring task. Actually, it is almost ...

September 17, 2019