Resources for Engineers

Listed below are a few resources that the staff of ExpressPCB uses and finds very helpful. You will find several vendors for components and engineering tools that we use in our work.

connectorPCB MFG Aids

Stevens Products Inc.provides edge protectors, Gold Finger Gloves, PCB Stiffeners, PCB Carriers, etc. Check out their products!

Submitted by our cool customer: Peter Capobianco “…audiophile and tube hi-fi DIYer extraordinaire…”

PCB Trace Width Calculator

This Javascript web calculator calculates the trace width for printed circuit boards based on a curve fit to IPC-2221 (formerly IPC-D-275).

PCB Via Calculator

This Javascript web calculator calculates the resistance, voltage drop, and power loss of printed circuit board vias. Note that vias are made out of plated copper which typically has a resistivity of 1.7E-6 to 2.2E-6 Ohm-cm. The calculator has an input box for the resistivity which defaults to 1.9E-6 Ohm-cm.

Tektronix TDS-1000


The Tektronix TDS-1000 is a great low-cost digital storage oscilloscope for the microprocessor developer. We have the old model TDS-220 and love it. The ability that storage scopes have to capture and display a single event make them extremely handy for micro controller development. This model’s very compact size also makes it great in the field. We do however consider that an analog scope may still be a better choice for doing sensitive analog work. These scopes are somewhat noisy at low voltages.

Mitutoyo Calipers

CalipersWhen laying out PC boards, it is very useful to measure small distances accurately. Selecting hole sizes for components requires measuring pin diameters in thousandths of inches. When placing pads for components or connectors with unusual lead spacing, it is necessary to carefully measure the pin layout. We have always been happy with Mitutoyo calipers for this job. We use both their dial and digital display models. A good selection of Mitutoyo calipers are available at McMaster-Carr. For the casual user, a no-name brand dial caliper is likely to be fine and cost under $50.


DigiKeyDigi-Key is a great resource for electronics components, such as semiconductors, resistors, capacitors, and connectors. They have a large inventory and ship very quickly. Their catalog often shows physical dimensions of parts, which is a big help when laying out PC boards. Many parts found in the ExpressPCB component library include Digi-Key part numbers.

Mouser Electronics

MouserMouser Electronics is very useful source for electronic components, particularly when prototyping. Their website and online catalog is an important source of technical information such as component data sheets.



Pic-Servo Motion Control

PicSrvoWe find that motion control projects are made easy using the PIC-SERVO. The PIC-SERVO is available either in a two chip set, or as a single board controller that includes the motor amplifier. It has a serial interface so it is easy to connect with a computer. The PIC-SERVO is probably the fastest and least expensive way to get a DC servo motor up and running. They also offer a stepper motor controller.

GetThePatendIf you are considering patenting a new invention or product, a great place to start your research is They offer a fast online tool for patent searches. Their database not only includes US patents, but also the patents registered in most European countries and Japan.

Envision Plastics

EnvPlasticsEnvision Plastics and Design offers an interesting enclosure solution for products to be manufactured in quantities from 50, up to a few thousand. Their plastic enclosures have a “consumer product” feel, but do not require expensive tooling or setup costs. This makes them a practical solution for small production runs.


Alta Via Technologies

AltaViaAlta Via Technologies is a high-end PCB design service. They specialize in laying out complex circuit boards for commercial, military, and medical applications. They offer significant expertise when working with PCB design issues such as high speed circuits (10Ghz +), high density SMT packages, and controlled differential impedance.


McMaster-Carr Supply

McMasterMcMaster-Carr Supply Company is a good source for mechanical parts. They have a complete selection of screws, nuts, washers and other fasteners. McMaster’s offers raw materials such as aluminum and plastics. They are also a good source for tools and machine shop supplies. They almost always have what you need in stock and ship very quickly.


Online Metals

OnlineMetalsOnline Metals is a very convenient source for purchasing small amounts of machinable metals and plastic. They have a good selection of aluminum in both sheet and plate, as-well-as delrin, nylon and acrylic. They will also cut to size.


AppCADAppCAD is a free RF design tool for Windows that can be downloaded at no cost from HP / Agilent. It is useful to help with the calculations for many RF, microwave, and wireless applications. PC board designers of RF circuitry will find the transmission line calculator handy. It also includes many computerized application notes relating to RF topics.