Controlled Impedance Through Cables And Connectors Impedance is a property of a transmission line, not of the metal in it. The energy that carries a signal at radio frequency travels in the field between the two conductors, guided by the dielectric that separates them, and it is the geometry of…

Laser Solder Ball Bonding for Flex Circuit Assembly Soldering a flex circuit with a conventional iron or with a hot air nozzle is a compromise. The iron contacts the joint and conducts heat into the polyimide, and the air nozzle heats everything within reach. Both methods put more energy into…

PCB Layout Workflow: From Schematic to Release A layout that is completed out of order costs time twice: once when the work has to be redone, and again when the board fails for a reason nobody anticipated. The sequence below is the one that consistently produces a releasable design, and…

Why The Board Came Back At The Wrong Characteristic Impedance A designer calculates a trace width for fifty ohms, sends the Gerber files out, and receives boards that measure a few ohms away from the target. Nothing in the design changed, and yet the number moved. The reason is that…

PCB Star Ground: One Point Everything Meets 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 Ground Return Via Placement: Where the Return Goes Down 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…

PCB Analog Digital Partition: Two Worlds on One Board Buyers and engineers often focus on the finished product and forget the production line behind it. In practice, most field failures can be traced back to process decisions made during assembly. Understanding PCB analog digital partition gives you a practical advantage…

PCB Split Plane Crossing: Stepping Over a Gap 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 split plane crossing from the perspective of a PCBA factory floor,…

Designing FPC Display Cables for Handheld Products A display cable inside a handheld product is one of the most constrained pieces of interconnect in the device. It has to fit into a gap a few millimetres wide, fold twice on its way from the main board to the panel, carry…

Solenoid Driver and Flyback Protection A solenoid is an inductor with a mechanical load attached, and every time the driver turns it off, the stored energy has to go somewhere. The choice of where that energy goes decides how fast the valve releases, how much stress the switch sees, and…