Eight Key Phases to the Engineering Cycle

On any given day in the United States there are more than 300,000 people working in the field of Electronics Engineering1. Many of these engineers are employed with fast-paced technology companies and are dedicated to churning out the latest gadgets for the consumer marketplace.  Some are employed by government agencies and are involved with projects to improve the performance of the vast arsenal of government electronics, satellites, communications and military efforts, while many others work tirelessly in specific market sectors.

Chuck Chase Director of Engineering

Chuck Chase
Director of Engineering

At MJS Designs, Chuck Chase is the Director of Engineering and, unlike many of his counterparts in the industry, he has a very unique electronics engineering role at MJS Designs.

While many engineers spend years, if not decades, on a single project, Chuck is able to apply his considerable knowledge and experience to the diverse projects that come through the doors at MJS Designs.  On any given day, Chuck could be working on an automatic flash system for a commercial camera, designing the circuitry for a military lighting project, developing a handheld ground fault sensor for the power industry, or even designing an ignition controller for a gas heating system.

Chuck, an Engineering Alumni of both Colorado State and Arizona State Universities, has worked with such companies as Motorola, McDonnell Douglas, and FLIR Systems.  Chuck has extensive experience in the areas of power circuits, projectile fusing, and aircraft avionics, and has spent considerable time focused on advanced perimeter security radar system design.  In fact, Chuck was a customer of MJS Designs for many years and was so impressed with their performance, when it was time to make a career change; MJS Designs was a logical choice.

“As a customer, I always loved having MJS Designs build my electronics assemblies.  Hardware built by MJS would fire up and work immediately without the need for debugging 99% of the time.  What a time saver!!  The success rate with other contract manufacturers was very poor in comparison.” – Chuck Chase

The average engineering project at MJS Designs lasts 3-5 months.  It goes without saying that some projects are completed quickly and some projects may take a year or more to complete the engineering segment of the project development.  There are always multiple active engineering projects at MJS Designs.  Chuck draws on long-standing relationships with engineering subcontractors as needed to help support these projects or when highly specialized expertise is required for a project.

In general, there are Eight Key Phases to the Engineering Cycle at MJS Designs.

The Engineering Development Cycle

1 – Quote Phase – In this early phase of the project, MJS makes initial contact with the customer and determines the level of effort that will be required to satisfy the customer’s project requirements.  This requires a significant amount of discussion and information exchange between MJS and the customer.  MJS Designs sees a wide variety of customers, some with nothing more than a general idea sketched out on a napkin who are seeking to build their first prototype, while others have an all-inclusive and highly-detailed list of functions, options and specifications that are required for a developing product or product advancement.

In addition, MJS Designs also works with companies who need reverse engineering. This comes about when a company wants to replicate a product or function, and the project design documents are out of date or nonexistent, and the original vendor or engineer is no longer available.

After an extensive review of the project requirements, a fixed priced quote is delivered to the customer – something that is unique in the industry.   A great deal of experience is required to accurately estimate an engineering project that is not fully defined and provide a fixed price quote.  Upon customer acceptance of the MJS Quote, the project moves to the Definition Phase.

2 – Definition Phase – This phase of the project further refines the project requirements and results in the generation of a product specification that defines the product that the customer will take delivery of.  Time is spent with the customer to gain a full and comprehensive understanding of the customer’s desired outcome, functionality options, long-term goals of the product and, of course, the budget parameters.    Once the customer approves the product specification the project moves to the design phase.

3 – Electrical/Mechanical Design Phase – Once all the specifications, desired outcomes and functionalities are clearly defined the schematic design work begins.  The schematic design is the fundamental piece of documentation for any electronics assembly.  A schematic shows the connection of components in a circuit in a way that is clear and standardized. It is a way of communicating exactly what components are involved in a circuit as well as how they are connected.  The schematics produced by MJS Designs will show component names and values, and provides labels for sections or components.  The completed schematic is then used to generate a BOM (Bill of Materials)  The schematic and BOM work together to fully define the electronic design.

A member of the MJS electrical engineering team will create a schematic design using one of the sophisticated electronic schematic capture tools available at MJS.   These tools include Altium Designer and several others.   The engineer may use other electronic tools to verify the electronic design.  These tools may include Spice Simulators, MTBF Calculators, Signal Integrity tools, and Power Calculation tools.

Some mechanical engineering may also be needed to satisfy the system requirements.  This usually involves the development of custom electronics enclosures, the development of custom molded plastic housings, or the modification of readily available COTS enclosures to meet the mechanical project requirements.  The MJS Engineering team works with a network of partner companies and contractors to satisfy mechanical project requirements.  This is usually done in parallel with the electronic design efforts.

Once the schematic and BOM documents are complete, the project is ready for “Fab” or fabrication of the bare printed circuit board (PCB).

4 – Printed Circuit Board Design & Fab Phase – The Engineering and PCB Design departments work together to generate a PCB design from the project schematic and BOM.  The PCB design is the process of placing the components on the PCB and then defining the actual copper trace that connects the electronic components to complete an electronic circuit.   Engineering and the PCB Designer will first place the components to achieve the system mechanical and electrical goals.  These goals may include placement of connectors to simplify cabling and system interconnect, meeting component height restrictions imposed by the electronics enclosure, and reduction of system noise to meet EMI/EMC standards.  Engineering will also provide other important information to the designer such as current levels in all parts of the design, special trace impedance requirements, special board labeling, mounting hole and test point specifications, etc.

In the case of Chuck Chase, at MJS Designs, Chuck often sits side by side with the PCB Designer to make sure the project requirements are met and the PCB Designer fully understands the desired outcome for the project.  Once the PCB design is complete, the customer is presented with the final PCB design for review and approval.   After approvals from engineering, design, and the customer, the bare PCB is fabricated and the PCB Assembly process begins.

5 – PCB Assembly Phase – The PCB assembly project phase involves the installation of the electronic components on the bare PCB.  There are a number of types of PCB Assembly offered at MJS Designs.  Many older boards use Through Hole technology that make use of components with leads that penetrate all layers of the PCB.  The most prevalent assembly type used today is known as Surface Mount Technology (SMT) which describes the method used to mount electronics on the surface of a printed circuit board.  Many SMT printed circuit boards include layouts for chip-scale packages.  An example would be the use of 0.4mm pitch microBGA packages.  SMT devices help conserve space on the smallest of circuit boards.  MJS also performs component installation for both leaded designs and lead-free assemblies which have become more and more popular over the years.

6 – Assembly Verification Test Phase – There are a number of tests that are performed during the PCB Assembly phase.  These include automated visual inspections to assure all components are oriented correctly and are connected and clean.  Depending on the requirements from the customer, the PCB may be inspected via x-ray or tested by Boundary Scan or Flying Probe The results of the tests may have the assembly team changing components to bring the assembly up to standard.   When the assembly phase is complete, the assembled boards are sent to engineering for Integration and Test.

6 – Integration & Test Phase – Once the assembly phase is complete, the electronics assembly is passed to Engineering for final evaluation.  Integration & Test refers to the process of installing any necessary firmware or embedded software (often newly developed) and ensuring the “programmed” assembly functions as specified by the product specification.  This is often an iterative process where the firmware/software is modified and re-tested on the hardware until the desired results are achieved.  This is usually a one-time engineering test using a limited number of boards.  The testing done during the Integration & Test phase is usually transferred to the higher volume Functional Testing by generating a Functional Test Procedure to be used by the Test Department.

7 – Functional Test Procedure Phase – An important and critical element in the Engineering Cycle is the completion of Functional Test procedures.  The Functional Test Procedure can be generated by either the customer or by MJS depending on customer needs and capabilities.  The Functional Test procedure defines the testing that is to be performed on all of the PCB assemblies as part of the factory acceptance testing.   It is important that the Functional Test Procedure is generated by a knowledgeable engineer who understands what tests need to be performed to ensure the electro-mechanical system performs as defined by the product specification.

8 – Functional Testing Phase – The MJS Test department will perform Functional Testing with support from the Engineering team as needed.   Electronics subassemblies can be tested as stand-alone systems, or, if the actual system is available, then the PCB assembly can be installed and tested within the actual product.  Often the Functional Testing is performed over a range of temperatures, voltages, and other conditions.  The assemblies may also be subjected to special testing such as shock, vibration, EMI, EMC, Safety, HALT, and others depending on customer requirements.   These special tests are done with support from outside test facilities that MJS routinely contracts with.  The objective of all of the testing is to assure the PCB assembly and product will perform as desired with high reliability when in the hands of the end consumer.

Summary

At any given juncture in the Engineering Cycle, MJS Designs maintains proactive communication with the customer and stands ready to do as much or as little as any customer needs for their engineering project.

MJS Designs has used the slogan “From Prototype to Production” for many years.  This one thought captures the overall Engineering Cycle with full turn-key, fast-turn services all under one roof, so the customer can deal with one team and not have to track each step of the process through different providers.

The following chart shows the variety of engineering services available through MJS Designs.  MJS technology specialties and experience are also summarized.

 

Engineering Services:

  • New Electronic Circuit Design/Analysis
  • Existing Electronic Circuit Analysis
  • Embedded Software Development
  • High Level/GUI Software Development
  • Electronic System Failure Analysis
  • Reverse Engineering
  • System Engineering
  • Thermal Analysis
  • Functional Test Development
  • Boundary Scan Test Development
  • Flying Probe Test Development
  • Mechanical Package Design
  • Mechanical Engineering Design/Analysis
  • Printed Circuit Board Design
  • DFX Analysis (Including DFM & DFT)
  • Technology / Obsolescence Update
  • RoHS Conversion
  • Production Cost Analysis
  • Engineering Documentation (Specs, Test Procedures, etc.)

Contact us today to schedule a time to discuss your ideas with the Engineering Team at MJS Designs or live chat with an expert at www.mjsdesigns.com.


References

1Bureau of Labor Statistics, U.S. Department of Labor, Occupational Outlook Handbook, 2014-15 Edition, Electrical and Electronics Engineers.