Bismuth Solder Alloys for Thermal-Sensitive Assembly Some assemblies contain parts that simply cannot survive a conventional reflow profile: an electrolytic capacitor with a limited rating, a sensor with a plastic body, or a module whose internal joints would remelt. Bismuth solder alloys offer a way out, because they melt near…

MI And CAM: What Happens After Gerbers Arrive Sending a set of gerber files to a fabricator starts a process that most designers never see, and the questions that come back a day later are the visible part of it. Behind those questions sit two engineering functions: the CAM department,…

PCB Panelisation Design Rules for SMT Assembly Lines A bare board cannot be assembled by itself. It needs a frame that the conveyor can grip, holes the machine can locate, and a way to separate the finished product without cracking it. Panelisation is the art of arranging circuits on a…

Shenzhen PCB Assembly: Capability, Process and Cost Factors The concentration of electronics manufacturing in one region has practical consequences for a buyer, and not all of them are about price. Component availability, process breadth and the depth of the supplier base all shape how an assembly programme runs. This guide…

What Ages a Conformal Coating and How to Slow It A conformal coating is chosen to protect a circuit board from its environment, and then the environment slowly destroys the coating. High and low temperature, ultraviolet radiation and chemical exposure all act on the polymer, changing its molecular structure and…

Measuring Impedance Matching with a Vector Network Analyzer A vector network analyzer is the instrument that turns an argument about matching into a measurement. It sweeps a known signal into a device, records what comes back, and reports the result as complex impedance across frequency. For anyone designing an RF…

Schematic Design Steps Before PCB Layout Begins The schematic is where most layout problems are created, because a decision that is cheap on a drawing can be expensive on a board. Reference designators, net naming, test access and the split between supply domains all originate here. This guide describes the…

Y1 Safety Capacitor Selection for Compact Power Inputs At the mains input of any product there is a small component whose failure mode is a safety event rather than a functional one. A safety capacitor connected between the line and the chassis carries the common mode noise that would otherwise…

Analog Design Questions That Reveal Board Level Mistakes Analog questions are useful in a design review because the answers reveal whether a team understands the board or only the schematic. A circuit that simulates perfectly can fail on a board because of a ground return, a decoupling assumption or a…

Verifying PCB Impedance with TDR Measurement Techniques Controlled impedance is a promise made in the stackup drawing and verified somewhere far downstream, usually with a time domain reflectometer and a coupon that travels with the panel. The measurement looks simple on a screen, yet the number it produces depends on…