Semiconductors

Semiconductors are where a circuit does its real work — switching, amplifying, converting and controlling. This range spans both families: discrete semiconductors such as diodes, transistors, MOSFETs and thyristors, and integrated circuits from logic and op-amps to voltage regulators and microcontrollers, plus the semiconductor hardware to mount and cool them.

Choosing semiconductors

How do I choose the right transistor or diode?

Start with the job. For a diode, match the reverse voltage and forward current, then pick the type — rectifier, Schottky, Zener or signal — for the behaviour you are after. For a transistor, weigh a BJT (current-driven and simple, good for small-signal work) against a MOSFET (voltage-driven and efficient, the usual pick for switching power), then check the voltage, current and power ratings, the gain or on-resistance, and the package. Keeping a margin below the maximum ratings, rather than working a part at its limit, is what makes it last.

Do semiconductors need heatsinking?

Any device dissipating real power does. A semiconductor turns some of what passes through it into heat, and once the junction temperature climbs too high the part can fail without warning. Small-signal devices usually manage on their own, but power transistors, regulators and rectifiers often need a heatsink, the right mounting kit and sometimes an insulating washer to move that heat away. For fans and larger cooling, see thermal management. Checking power dissipation against the package rating early saves a redesign later.

How do you handle obsolete or hard-to-find parts?

Semiconductors are where obsolescence bites hardest, moving through their life cycle faster than passives do. Where an exact device is no longer made, cross-referencing to a functional equivalent — matched on voltage, current, package and pinout — is usually the quickest way forward, and the breadth of the range makes that easier. Everything is traceable and carries the datasheets and compliance data needed to qualify a part for manufacture, whether you are buying one to prototype or reels for the line. Sourced next to passives and the rest of the components catalogue, it all sits on one account.