PCB Solder Paste Control: Holding It Steady Modern electronics depend on boards that are assembled correctly the first time. Every product – a phone, a charger, a medical instrument or an industrial controller – relies on thousands of solder joints that must conduct current for years. This article explains PCB…

PCB Enclosure Fit: Does the Board Go In Electronics manufacturing has become a discipline of small details. Solder paste volumes, placement accuracy, temperature profiles and inspection limits all add up to the final result. This guide looks at PCB enclosure fit from the perspective of a PCBA factory floor, covering…

Crystal Oscillator: Design Rules and Process Limits A crystal oscillator is a mechanical resonator with a very high quality factor, and the circuit around it is an amplifier that has to keep it running. It is also one of the few analog circuits left on a digital board, and the…

PCB Baking Schedule Before Assembly Circuit board laminate absorbs water from the air, and the amount it holds depends on the material, on the humidity, and on how long the board has been exposed. That moisture becomes a problem at reflow temperature, because water turns to vapour and expands, and…

AOI Program Setup and the Defect Library Automated optical inspection is a camera and a decision. The camera is reliable; the decision depends on how the AOI program was written and on what it was taught to accept. Two machines with identical hardware will find very different numbers of defects…

Tin Whisker Growth and Mitigation on Plated Surfaces A thin filament of metal growing out of a plated surface, apparently spontaneously, is one of the strangest reliability problems in electronics. Tin whiskers can grow several millimetres long, they conduct electricity, and they can bridge gaps that were designed with generous…

Reflow Profile: Reflow Profiling with a Thermal Coupon on the Real Board A reflow profile is a claim about what the board experiences, and the claim is only true where it was measured. An oven display shows the air temperature in each zone, which is not the same as the…

Development Board PCB Design for Embedded Platforms A development board exists to expose every interface of a processor, which makes it a different design problem from a product. Development board pcb design is judged by how many interfaces reach a connector and how easily the software team can reach them.…

Random Vibration Testing for PCB Assemblies and Components A board that survives a drop test can still fail on a shaker table, and a board that survives a shaker table can still fail in a vehicle. Vibration is a cumulative loading process, and the damage it does depends on the…

PCB Chassis Grounding: Bonding to the Case Electronics manufacturing has become a discipline of small details. Solder paste volumes, placement accuracy, temperature profiles and inspection limits all add up to the final result. This guide looks at PCB chassis grounding from the perspective of a PCBA factory floor, covering bonding…