Printed Circuit Board Testing Methods

Printed Circuit Board Testing Methods

Printed Circuit Board Testing Methods
Printed Circuit Board Testing Methods

To improve the production and assembly process of the PCB we at Argus technologies follow a wide variety of Printed Circuit Board Testing Methods and PCB testing tools to maintain PCB standards. We maintain best PCB testing procedures to maintain zero defect products. Some of the best PCB testing methods or PCB failure analysis test and testing tools were used in Argus defined and followed PCB testing process. The tested PCB has the highest success rate and offers an advantage for all customers and users equally. There are various Printed Circuit Board Testing Methods, below we are trying to capture commonly used methods and which are found to be most effective in testing Printing circuit boards.

Types of Test Done on Printed Circuit Board

  1. Solderability Testing

The PCB manufacturing process can be the main source of assembly related issues. To minimize the probability of failure, many manufacturers test component, and PCB pad. Solderability is the process to ensure the robustness of the surface and increase the probability of forming a reliable solder joint and minimize the failure.
The solderability failure method evaluates the strength and the quality of wetting of a solder by reproducing the contact between the solder and the material.
Solderability testing can verify that the components will meet the requirements and quality standards.

Solderability testing works on a variety of applications, including:
PCB coating evaluation
Solder evaluation
Flux evaluation
Benchmarking
Quality control

  1. PCB Contamination Testing

Contamination can cause issues like the rapid deterioration of wire bond interconnects, including corrosion, degradation, and metallization. Contaminations’ represent one of the most common issues of part failure.

Many manufacturers employ aggressive chemical processes during PCB fabrication, including the following:

  •    Copper etching liquid
    • Hot air levelling fluxes
    • Electrolytic solutions
    • Water-soluble soldering

For the cleaning process, it requires chemicals to ensure the cleaning process. The electronics industry had introduced contamination testing. Which help in measuring the cleaning efficiency and stability of the cleaning process.
Contamination testing measures the amount of ionic contamination contained in a sample. The process of testing contamination involves
immersion of the PCB sample into solution. Ones it has been dissolved into the solution the ionic contamination, which causes a change in the constitution of the solutions and has a significant influence on the values or readings.
After findings, the readings the analyst plots the contamination level on a contamination testing and compare the value with the industry standards.

When the reading exceeds an established level it confirms that the manufacturer has a problem with the cleaning process. And it can cause detrimental effects, and be including corrosion and electro-chemical migration when the parts remain in the component. This technique can detect even the smallest parts.

  1. Optical Microscopy/Scanning electron microscopes (SEM)

Optical Microscopy is one of the preferred and best testing methods used for detecting the PCB faults and failures
which are associated with soldering and assembly. Optical microscopy is the best in speed and accuracy to find the faults of the PCB
the optical microscopy can reach up to 1000X has a small depth field and shows features in a single plane.
Sometimes PCB failure analysis requires more powerful magnification tools to detect the failure in the PCB.
SEM offers highly-effective testing techniques for performing semiconductor die failure analysis.
SEM Microscopes provides the detailed images at higher magnifications up to120, 000 X It is typical to have magnifications of 50,000 to 100,000 and feature resolutions down to 25 angstroms. This is one of the best methods to find the failures in the images for the analyst.

SEM Technology provides in-depth failure analysis with a three-dimensional view of the sample. It can also verify semiconductor die metallization, integrity, and quality. SEM also provides evidence of heat treatment and identifies the metal used.

  1. X-ray Inspection

This is the best powerfull tool for users for non-invasive failure analysis. Users have a choice of basic film X-ray, real-time X-ray and
3- dimensional X-ray systems, users can use these tools to detect actual or potential defects. With this tool, users can also inspect a PCB component that has hidden joints or parts located underneath a chip

With these basic X-ray inspection capabilities, technicians can conduct the following types of internal component examinations;

Internal particles
internal wire dress
die attach quality
voids in the sealing lid
substrate/printing wiring board trace integrity
insufficient excessive or poor solder

  1. Micro sectioning analysis

Micro sectioning is also known as Cross-sectioning and it refers to a printed circuit board testing methods used to investigate the PCB.

Thermomechanical failures
Component Defects
Opens or shorts
Processing failures due to solder reflow.
Raw material evaluations

In the micro sectioning, the failure analysis removes a 2-dimensional slice out of a sample which uncovers some of the features within the board. The micro-sectioning analysis provides a precise technique to the technician that isolates the relevant electronic component and removes parts from the sample PCB.
The advantage of this printed circuit board testing methods is the ability to position the sample on a flat surface and invest each part of its parts together.

We at Argus Technologies are specialized in Customized PCB Design services, PCB Assembly service, PCB Fabrication, Embedded Hardware, and software.   Please contact us for details and to get a free quote on our services.

Please follow and like us:

DATA ACQUISITION SYSTEM FOR FIBER BRAG GRATING SYSTEM

multilayer PCBs

Data acquisition system (DAQ) is an information system that collects stores and distributes information. It is used in industrial and commercial electronics, and environmental and scientific equipment to capture electrical signals or environmental conditions on a computer device.

DATA ACQUISITION SYSTEM FOR FIBER BRAG GRATING SYSTEM

Overview

The most straightforward means for interrogation of a FBG sensor element is to illuminate the
FBG sensor (s) by broadband source & the narrowband component reflected by the FBG is
directed to the wavelength detection system as shown in the below figure.
CCD is illuminated by the optical signals reflected by the FBGs. This implementation supports 8 CCD’s. CCD sensor using Argus developed FPGA controller board.
The FPGA used for the control of CCD processor is Xilinx FPGA — XC3SD1800A-
4CSG484C.

DATA ACQUISITION SYSTEM for fiber brag grating system

Hardware Implementation

  • Aligtron 1×8 Latching Fiber optic Switch (MEMS Latch)
  • InGaAs linear image sensor (Hamamatsu)
  • Image Signal Processor (AD9826)
  • Field Programmable Gate Array Logic (FPGA)
  • Programmable system on chip PSoC5LP)
  • SRAM Memory Unit for data storage
  • System Clock 25MHz
  • Single Power supply (9V, ~300mA)

Block Diagram of the Data Acquisition System Controller

Block Diagram of the Data Acquisition System Controller

Functional Description

  • Receives command bytes from PC to FPGA through UART protocol and act accordingly
  • Controls all the other peripherals in the “FPGA controller board” by providing required
    inputs to them.
  • Receives the signals from the sensor, & modifies them as required control signals for the
    ADC.
  • Receives 8 bit output from the ADC, makes it into 16 bit word & stores in its memory.
  • Sends this 256 * 16 bit words (each pixel voltage in binary) to the Programmable system on
    chip (PSoC5LP – CY8C58LP).
  • Finally, the data stored in the PSoC is displayed on the PC or any other host devices through
    USB by using Lab View software (version 14.4).

Flow of the Hardware

Flow of the Hardware

Key Features

  • Used for detecting the narrow band signal from a broad band source i.e. of infrared rays &
    near visible signals.
  • Supports protocols such as UART, USB, FLASH
  • Synchronous Design
  • System clock speed used is 25 MHz.
  • Design is implemented using Verilog HDL

Advantages

  • Silicon Proven on Xilinx FPGA Spartan-3A DSP (XC3SD1800A-4CSG484C) using ISE
    14.3 and higher versions.
  • The spartan-3A DSP FPGA combined with proven 90nm process technology which delivers
    more functionality and bandwidth.
  • Set up is handy to carry and even give accurate results in sampling the CCD waveform.
  • Customizable with easy integration.
  • Gate count is approximately 1150 logic cells

Argus technologies is specialized in offering Customized product design service which can be on turnkey basis or with limited involvement in the project. Our core expertise lies in area of Product Design, Electronic manufacturing, Embedded Software Development, PCB Layout Design Service, Contract manufacturing including prototype to production and highly specialized software development in embedded domain.

Please follow and like us:

Printed Circuit Board Design

Printed Circuit Board

Printed Circuit Board

 

Printed Circuit board or PCB is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate.

PCBs can be single-sided (one copper layer), double-sided (two copper layers on both sides of one substrate layer), or multi-layer (outer and inner layers of copper, alternating with layers of substrate). Multi-layer PCBs allow for much higher component density, because circuit traces on the inner layers would otherwise take up surface space between components.

 PCB is Made of

A basis PCB starts with a copper-clad fiberglass material or thin copper sheets attached to either side of board. It consists of.

  • Copper Foil
  • Copper plating
  • Solder Flow
  • Solder Mask
  • Trace
  • Slots and Cut-outs

PCB Fabrication

  • Basic Steps for PCB design
  • Set-up
  • Imaging
  • Etching
  • Drilling
  • Masking
  • Silk screening
  • Route
  • Electrical Test

Different Types of Printed Circuit Boards

 

 

 

Types of printed circuit boards

PCB have copper tracks to connect the holes where the various components are located they are specially designed for each and every circuit and build construction very easy. Though, making the PCB necessitates special tools. The different types of printed circuit boards mainly include the following.

Single Sided Printed Circuit Boards

single sided PCB board
This type of printed circuit board contains just one layer of substrate or base material in this Single sided PCB one side of the substrate is covered with a thin layer of metal in this Copper metal is an excellent electrical conductor. The protective solder mask sits on the top of the copper layer and a silkscreen coat may be applied to the top of the mark parts of the PCB board.

Single-sided PCB has electronic components and circuits on only one side. This board works best for simple electronics or they can be used in very complex devices like

  • Power supplies
  • Relays (automotive and industrial)
  • Timing circuits
  • Sensors products
  • Led lighting radio and stereo equipment
  • Packaging equipment
  • Surveillance
  • Calculators
  • Printers
  • Coffeemakers
  • Vending machines
  • Solid state drives
  • Camera systems

Benefits of having single sided PCBs

Lower cost: single-sided PCBs especially for high volume orders the cost of manufacturing and producing single sided circuit boards are very cost-effective and affordable due to the basic designs.

Lower probability of manufacturing issues there will undoubtedly be fewer problems during the manufacturing stage Due to these manufacturers produce these boards at higher volumes at faster pace with the company standards.

Double Sided Printed Circuit Boards

Double sided PCBs

Double sided pcbs is the extension of single sided PCB when a single sided not enough it will go to the other side there will be conductor /line on both two sides.

Double-sided PCBs have a conductor pattern on either sides of the board having two separate conductor patterns needed an electrical connection between them. this electrical bridges are called ‘vias’ via is a hole in the pcb that filled or plated with metal and touches the conductor pattern on both sides of the pcbs.

Where we can use Double sided Printed Circuit Boards

There are a countless old and new double sided designs silver and gold finishes, ultra high copper, high and low temperature solder coated are the few examples of double sided PCBs boards.

Some are the applications of Double Sided PCBs

  • Power supplies
  • Converters
  • Control relays
  • Regulators
  • Led lighting
  • Phone systems
  • Line reactors
  • Test equipment
  • Amplifiers
  • Traffic systems
  • Automotive dashboards

Advantages of having Double sided PCB

  • Relatively lower cost
  • Reduced board size
  • Increased circuit density
  • Highly flexibly for designers

Multi-layer Printed Circuit Boards (PCB)

multilayer PCBs

The Multi layer PCB Boards is made with three or more conductive copper foil layers this appears as several layers of double-sided circuit boards to increase the space available for wiring. This can be achieved by laminating and glued the double sided circuit boards together with insulating layers in between. The entire process is done so that two layers are placed on the surface sides of the PCB to connect the environment and all the electrical connections between the layers are achieved with vias. Since the layers in a PCB are laminated together it’s often difficult to tell how many there are but u inspect the side of the board u may able to see them.

PCBs are becoming popular in electronics. They come in a wide range of sizes and thicknesses to accommodate the needs of their expanding applications they are ranging anywhere from four to twelve layers and are no more cost-effective to produce Application like mobile device and Smartphone tend to use around twelve layers.

Advantages of having Multilayer PCBs

  • Small in size
  • High Quality
  • Increased Durability
  • More Powerful
  • Single connection point

Where we can use the multi layer PCB

  • Consumer electronics
  • Computer Electronics
  • Telecommunications
  • Industrial
  • Military and Defences
  • Automotive
  • Aerospace

We at Argus Technologies are specialized in Customized PCB Design services, PCB Assembly service, PCB Fabrication, Embedded Hardware, and software.   Please contact us for details and to get free quote on our services.

Please follow and like us: