Monthly Archives: April 2013

What is a Burn-in Board?

Burn in Board is a printed circuit board which functions as a jig in the Burn-in process. The Burn-in Board is used as part of the ASIC reliability testing process during which components are stressed to detect failures. Burn in Boards consist of sockets to accommodate the tested ASICs and are designed to withstand the hot temperatures during tests.


Burn in Test

Burn in tests check the reliability of the ASIC device and are typically done at 125ºC, while electrical signals and power are applied to ASICs. Burn-in boards are inserted into the burn-in oven which supplies the necessary voltages to the samples while maintaining the oven temperature at 125ºC. After the stress testing the samples must be screened to ensure they passed the oven testing.



Burn in Board Materials

Burn in boards utilize high grade materials. For testing up to 125C a special version of FR4 is used (High Tg FR4). For higher temperatures up to 250C a Polyimide is used; and for very high temperatures up to 300C a High grade polyimide is used.



Burn in Board Design

In addition to the typical PCB design guidelines which are quite common among all PCB designers, there are a few additional factors for making a Burn in Board. One of the most important considerations is selecting the highest possible reliability and quality for the Burn in Board and the test socket. You don’t want your Burn in board to fail before the device under test. Therefore, all active/passive components and connectors should comply with high-temperature requirements, and all materials and components should meet high-temperature and aging requirements.


Get instant price quote for your Burn in Board: Click Here

Synopsys Mergers and Acquisitions History [infographic]

The following infographics shows Synopsys’s mergers and acquisitions along the years from its very beginning. Synopsys was founded in 1986 by David Gregory, Aart de Geus and has been involved with many mergers and acquisitions.



The very recent large acquisitions include:


  • Synplicity
  • ChipIT


  • ChipIdea


  • VaST
  • CoWare
  • VirageLogic
  • Optical Research


  • Nsys
  • Extreme


  • Luminescent (Mask BU)
  • Magma
  • SprintSoft

synopsys acquisitions


Die Per Wafer Formula and (free) Calculator

Calculating the number of Dies Per Wafer (DPW) is a very simple and straight forward task. It’s actually based on basic high school mathematics which are related to circle area formula, remember Pi?

Silicon dies which are placed on a wafer can also be described as many squares placed inside a circle — thus the calculation is about first finding the overall circle area using both the mathematical number Pi (approximately equal to 3.14159) and the wafer size.

The wafer size and the die size are known in advance, however, as our “squares” have spaces between them (e.g. scribe lines) and the area located at the edge of the wafer cannot be used, the calculation is a bit tricky, therefore, some recommend using the Die Per Wafer tools results as an estimation rather than a calculation.


In addition to the above unused area, the foundry will use additional area for testing purposes (PCM structures) that will eat up relatively small size of the wafer. Sawing lanes, wafer margin and test structures size vary from process node to process node and from foundry to foundry. Therefore, is it highly recommended to have the final DPW figure directly from the foundry because they have all the knowledge and information required to provide the actual figure.


AnySilicon’s Die Per Wafer free Tool

Our free Die Per Wafer calculator is very simple and based on the following equation:

die per wafer formula

d – wafer diameter [mm] (click her for wafer size information)

S – die size [square mm]

For your convenient, we have placed the Die Per Wafer calculator as an online Excel sheet so you can use it online or download it into your ASIC price calculator.


To make life a bit easier we are offering a simple downloadable Excel calculator that helps calculate die per wafer for different wafer and die size. Download free DPW Calculator


What’s next?


Get price quote for ASIC design services here.

Or get wafer price proposals from vendors here.