An Illustrated History Of Printed Circuit Boards

The first printed circuit board (PCB) was developed in the 1930s by Paul Eisler, who studied engineering and was a magazine editor before taking up the field of electrical engineering. Eisler had the idea that printing on paper could be used for more than just newspapers. He developed the idea in a tiny one-room flat in Hampstead, London.

Moe Abramson

The history of printed circuit boards has been influenced by many technological developments. Some of the first PCBs were created by Moe Abramson, a computer engineer who helped develop the auto-assembly process. Abramson also developed copper foil interconnection patterns and dip soldering techniques. His process was later improved upon, and his work led to the standard process of manufacturing printed circuit boards.

The printed circuit board is a circuit that mechanically supports and electrically connects electronic components. It is typically made from two or more layers of copper sheets. Its manufacturing process allows for higher component density. It also has plated-through holes for electrical connections. More advanced PCBs also incorporate embedded electronic components.

Stanislaus F. Danko

The history of printed circuit boards dates back to the mid-20th century. Before that, electronic components had wire leads and were soldered directly to the PCB’s trace. The first auto-assembly process was developed by Moe Abramson and Stanislaus F. Danko, who were members of the U.S. Signal Corps. They patented this process, and it has since become the standard method of printed circuit board fabrication.

Printed circuit boards are an important part of electronic devices. From their humble beginnings in the mid-19th century, they have become commonplace. Their evolution has been driven by rising consumer demands. Today’s consumers expect instant response from their electronic devices. In 1925, Charles Ducas developed a process called “printed wire” to reduce the complexity of wiring. Dr. Paul Eisler built the first operational PCB in Austria in 1943.

Harry W. Rubinstein

The history of printed circuit boards has been largely shaped by a man named Harry W. Rubinstein, who served as a research scientist and executive with Globe-Union’s Centralab division from 1927 until 1946. Rubinstein was responsible for several innovations while at Centralab, including improved roller skates, spark plugs, and storage batteries. However, his most famous invention was the printed electronic circuit.

The history of printed circuit boards starts in the early 1900s, when electronic components used to be soldered onto a PCB. The PCB had holes for wire leads, and the leads were inserted through those holes and then soldered to the copper traces on the board. However, in 1949, Moe Abramson and Stanislaus F. Danko developed a technique that involved inserting component leads into a copper foil interconnection pattern and dip soldering them. This process was later adopted by the U.S. Army Signal Corps, and eventually became a standard way to fabricate printed circuit boards.

Surface mount technology (SMT) components

SMT is a technology that allows electronic components to be applied directly to the surface of a printed circuit board (PCB). This allows for more efficient production and a more compact design. It also reduces the number of drilled holes, which can result in a lower production cost. SMT components are also more robust and can withstand higher levels of vibration and impact.

The major advantage of surface-mount technology over through-hole components is that it is highly automated and reduces the number of failures during the welding process. In addition, SMT components are much cheaper to package than their THT counterparts, which means the selling price is lower. This is a huge advantage for those clients who are looking for large-volume printed circuit boards.

Multiple layers of copper

PCBs with multiple layers of copper are constructed from multiple layers of copper foil and insulating material. The copper layers may represent a continuous copper area, or they may represent separate traces. The conductive copper layers are connected to each other using vias, which are thin channels that can carry current. These conductive layers are often used to reduce EMI and provide a clear current return path. Listed below are some benefits of using copper on printed circuit boards.

Multilayer PCBs are more costly than single-layer boards. They are also more complex to manufacture and require a more complicated manufacturing process. Despite the high cost, they are popular in professional electronic equipment.

Elektromagnetisk kompatibilitet

Electromagnetic compatibility (EMC) is an important aspect of a product’s design. EMC standards are a prerequisite for ensuring safe operation of products. The design of a PCB must be electromagnetically compatible with its components and environment. Typically, printed circuit boards do not meet EMC standards on the first pass. Therefore, the design process should be centered on meeting EMC standards from the beginning.

There are several common techniques to achieve electromagnetic compatibility. One method involves putting a ground layer on a PCB. Another method involves using ground grids to provide low impedance. The amount of space between the grids is important in determining the ground inductance of the circuit board. Faraday cages are another way to reduce EMI. This process involves throwing ground around the PCB, which prevents signals from traveling beyond the ground limit. This helps reduce the emissions and interference produced by PCBs.

Problemer med loddekugler i BGA-komponenter og deres afhjælpning

Problemer med loddekugler i BGA-komponenter er almindelige problemer, der kan føre til forringelse af komponenterne. Problemerne skyldes delaminering eller oxidering af loddekuglerne. Heldigvis er løsningerne enkle og kræver ikke nogen kompleks teknisk viden. Disse løsninger vil hjælpe dig med at forhindre yderligere skader på dine komponenter.

Delaminering af loddekugler

BGA-komponenter er tilbøjelige til at få problemer med loddekugler, ofte kaldet "head-in-pillow defects". Problemet opstår, når to metaloverflader forbindes mekanisk, ofte med en loddekugle. Mængden af kontakt mellem kuglen og loddetinnet varierer afhængigt af loddeprocessen og den varme og det tryk, der påføres delene. Der er foretaget flere undersøgelser for at forstå årsagen til denne defekt og løsningerne til at forhindre den.

En defekt BGA kan have alvorlige konsekvenser for produktets funktionalitet. En typisk løsning er at udskifte den berørte komponent med en ny. Men denne løsning kan være problematisk og dyr. Et bedre alternativ er at reball'e BGA-komponenten. Det kræver, at en tekniker fjerner de berørte komponenter og installerer nyt loddetin i de blottede områder.

For at undgå problemer med loddekugler er det vigtigt at bruge den rigtige teststikdåse. Der findes to typer teststik: kloformede stik og nålespidsstik. Førstnævnte får loddekuglen til at udvide sig og blive deformeret, mens sidstnævnte forårsager stød og slid på loddekuglen.

Oxidation af loddekugler

Problemer med oxidering af loddekugler på BGA-komponenter er et voksende problem inden for elektronikproduktion. Disse defekter skyldes ufuldstændig sammensmeltning af BGA/CSP-komponentens loddekugler med smeltet loddepasta under loddeprocessen. Disse defekter påvirker både blyfri og tin-bly-loddede samlinger. Der er dog måder at afhjælpe disse problemer på.

En måde at undgå dette problem på er at bruge loddepasta, der er halvflydende. Det sikrer, at kuglen ikke kortslutter, når den opvarmes. For at sikre en solid loddeforbindelse vælges den anvendte loddelegering omhyggeligt. Denne legering er også halvflydende, hvilket gør det muligt for de enkelte kugler at forblive adskilt fra deres nabokugler.

En anden måde at forhindre oxidation af loddekugler på er at beskytte dine BGA-komponenter under håndtering. Når du transporterer eller sender, skal du sørge for, at dine BGA-komponenter placeres i en ikke-statisk skumpalle. Det vil forsinke oxidationsprocessen af loddekugler og sokler.

Fjernelse af loddekugler

Fjernelse af loddekugler til BGA-komponenter er en kritisk proces. Hvis loddekuglen ikke fjernes korrekt, kan BGA-komponenten blive beskadiget og resultere i et rodet produkt. Heldigvis er der flere måder at fjerne kuglen fra BGA-komponenter på. Den første måde er at bruge et vakuum til at fjerne eventuelle lodderester. En anden måde er at bruge en vandopløselig fluxpasta.

I mange tilfælde er den mest omkostningseffektive metode reballing. Denne proces erstatter blyfri loddekugler med blyholdige. Denne metode sikrer, at BGA-komponenten bevarer sin funktionalitet. Processen er meget mere effektiv end at udskifte hele printkortet, især hvis komponenten bruges regelmæssigt.

Før processen påbegyndes, bør en tekniker undersøge BGA-komponenter. Før han eller hun rører ved enheden, skal han eller hun vurdere loddekuglernes størrelse og form. Desuden skal han eller hun bestemme, hvilken type loddepasta og stencil der skal bruges. Andre faktorer, der skal overvejes, er typen af loddemetal og komponenternes kemi.

Omlodning af kugler

Lodning af BGA-komponenter er en proces, der involverer omarbejdning af elektroniske samlinger. Denne proces kræver reflow-lodning og en stencil. Stencilen har huller, som loddekuglerne passer ind i. For at opnå de bedste resultater er stencilen lavet af stål af høj kvalitet. Stencilen kan opvarmes med en varmluftpistol eller en BGA-maskine. Stencilen er nødvendig for BGA reballing-processen og hjælper med at sikre, at loddekuglerne passer ind på de rigtige steder.

Før en BGA-komponent reballes, er det vigtigt at forberede printkortet til processen. Det vil forhindre skader på komponenterne. Først forvarmes printkortet. Det gør det muligt for loddekuglerne at blive smeltet. Derefter tager robotten en række komponenter fra en matrixbakke. Den påfører flux på loddekuglerne. Derefter kører den gennem et programmeret forvarmningstrin. Derefter fjerner en dynamisk loddebølge de uønskede kugler fra printpladen.

I mange tilfælde er det mere økonomisk at reball'e en BGA-komponent end at udskifte hele printkortet. Udskiftning af et helt printkort kan være dyrt, især hvis det bruges i maskiner, der kører regelmæssigt. I sådanne tilfælde er reballing den bedste løsning. Ved at udskifte loddekuglerne med nye kan printkortet modstå højere temperaturer, hvilket forbedrer printkortets levetid.