IPC-A-610 and J-STD-001 Acceptance Criteria Compared Two documents govern most electronics assembly work, and they are frequently confused. IPC-A-610 describes what a finished assembly should look like, while J-STD-001 describes how it should be made. One is an inspection standard and the other is a process standard, and knowing which…

PCB Design Key Points: Routing, Ground and Decoupling Most of the problems that appear in a finished board trace back to a small number of pcb design decisions taken early: how the signal flows, where the ground reference is, how the supply is decoupled and how much space the routing…

Hand Soldering A QFN: Step By Step A QFN package has no leads to solder. Its connections are flat pads on the underside of the body, arranged around the perimeter, with a large exposed pad in the centre that serves as both the thermal path and, usually, the ground connection.…

In-Circuit Test Fixture Design: Probes, Access and Maintenance A bed of nails fixture connects every net on a board to the tester through a spring probe. The design of that fixture determines whether the test is reliable, maintainable and worth the cost of building it. What the Fixture Must Do…

PCB Oven Verification: Key Process and Quality Checks 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 oven verification from the perspective of a PCBA factory floor, covering…

PCB Component Kitting Accuracy: From Design to Repeatable Production 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…

Pcb Design Software: Preparation, Placement and Process Control Choosing a pcb design software package is a decision that outlives the project it is made for. The tool holds the library, the constraints and the fabrication output, and changing it later means migrating all three. What matters is not the length…

Laser Welding for Server Liquid Cooling Plates A liquid cooling plate for a server has to do three things at once: conduct heat from a cold plate or a die into the coolant, contain that coolant at pressure for the life of the machine, and do it with an internal…

Isolation Amplifier Current Sensing Design Measuring current in a motor drive, a battery system or a mains connected converter means placing a sensing element at a potential that would destroy the controller connected to it. An isolation amplifier solves that problem by transferring the measurement across a barrier, and the…

Fine Pitch SMT Production: Six Problems That Appear At Volume Fine pitch surface mount parts pass every sample build and then fail in volume. The reason is that a sample is assembled with attention and a small number of pieces, while a production run is assembled with the process settings…