Archive for the ‘01 Data Preparation’ Category

Etch Factor

Sunday, February 10th, 2013

An etch factor or etch compensation is a process modification made by the Printed Circuit Board (PCB) manufacturer to compensate for the chemical etching process. The chemical etching process is a subtractive operation that removes copper gradually when forming the circuit pattern. The size of the features at the end of the process are smaller than the size of the features at the beginning of the process. When a PCB design requires a track width of 0.005″ (0.127 mm) the PCB manufacturer has to start out with a wider track. The amount the track is increased by is referred to as an etch factor or etch compensation. The etch factor is also proportional to the thickness of the copper or copper weight weight being removed. The more copper being etched through the larger the etch factor.

Etch factor added with CAM tool.

Etch factor added with CAM tool.

The fact that the PCB manufacturer has to increase the feature size to compensate for their manufacturing process is critical for a PCB designer to understand. The designer must provide enough spacing in their design for the PCB manufacturer to process the design. In other words, the minimum spacing in the design must meet the manufacturer’s minimum space that they may consistently process. In PCB manufacturing there are three types of spacing that we consider. They are… (more…)

Data Preparation: Front End Engineering

Sunday, November 21st, 2010

Printed Circuit Board fabricators all have a Front End Engineering group. How the group is organized and what they are called differs from manufacturer to manufacturer. The task remains the same. They are tasked with taking in customer designs and converting them into tooling for use by the manufacturing plant to build the customer’s design. Front End Engineering of a printed circuit board manufacturer consists of at least three core disciplines… (more…)

Data Preparation: Data Formats

Sunday, December 13th, 2009

The first step in the manufacturing process of a printed circuit board is commonly referred to as data preparation. This is an operation in which information provided by the customer or designer is converted for use by the manufacturer to build the pcb. There are standard data formats required by the bare board manufacturer. The commonly accepted formats are as follows… (more…)