Test Data Out (TDO)

The Coming Crisis in Board Bring-Up

I was reflecting on how much processor speeds, memory, and data transmission rates have increased over the last few decades. And yet the same old tools and techniques are often used to bring up new designs. When do you think we fall off the cliff?

P1838: the 3D Standard and its use with 1687

One of the newest IEEE Standards Committees is currently defining the P1838 3D Test Standard. The main goal of P1838 is to develop a “Per Die” Access Mechanism that becomes a “Stacked Die” Access Mechanism when the individual die are stacked into 3D silicon. The main focus is to handle the configuration of stacking die that are connected to each other using Through-Silicon-Vias (TSV’s) to make 3D silicon integration, which is different from Package-on-Package and other 3D packaging techniques. Find out more…

Board Bring-Up

Board bring up of an early prototype is one of the most important steps for a design team. The first boards must pass through a battery of tests to demonstrate that the hardware is rock-solid. Non-intrusive technologies can be used to accelerate this process.

What is JTAG? and What is IJTAG?

I’m sometimes asked how JTAG, IJTAG and boundary scan all relate to one another. Here’s a short explanation.

IEEE P1687 and In-Circuit Test (ICT)

I read an interesting paper recently suggesting that IEEE 1687-based tests were best run at ICT on the manufacturing floor. The article was, of course, written by an ICT vendor. This is patently not true and is even a little bit preposterous. Let me explain…

The test stack

Those of you with a telecom background are no doubt aware of the “OSI Network Model”, also known as the OSI pyramid or stack. It is a way of sub-dividing a communications system into smaller parts called layers. A layer is a collection of similar functions that provide services to the layer above it and receives services from the layer below it. A decade ago, the telecommunications test industry underwent a revolution when platforms emerged that could cover multiple layers of the OSI stack. Now, the same thing is happening in the circuit board test industry...

Test coverage using multiple technologies

It is a well-known fact that manufacturing test strategies must involve a combination of inspection, structural, and functional test technologies in order to yield highest quality and minimize customer returns. But a new breed of non-intrusive, software-based technologies promises to disrupt legacy test solutions by guaranteeing the highest test coverage at the lowest cost. These technologies leverage off of the embedded instruments within silicon to achieve this goal in the following ways...

A week at ITC

Last week, ASSET was in attendance at the International Test Conference (ITC) in Austin, TX. ITC is the cornerstone of “Test Week”, a premiere technical event which addresses the challenges of providing high-quality, cost-effective test solutions for chips, boards and systems. ASSET had one of the largest booths at the Exhibition and we also contributed to tutorials, advanced industrial practice sessions, poster sessions, workshops, and a host of professional fringe meetings.

Who will use IEEE 1687?

Who gets the benefit of using IEEE 1687 (IJTAG)? The simple answer is, “there is something for everyone!”

Once organizations and engineers have been exposed to IEEE P1687 IJTAG, the Proposed Draft Standard for Access to Embedded Instruments, and no matter which part of the semiconductor-based product lifecycle they are involved with, they all seem to find something that excites them. The IEEE 1687 standard resonates with engineers and managers because it either solves a technical problem, it provides a cost advantage, it reduces the amount of work, or it enables automation of some (onerous) task…

What is IEEE 1687?

Hello, and welcome—this is the first of a set of short blogs on the topic of 1687. Since 1687 is still in the proposal stage, it is actually referred to as P1687 right now, but the “P” will disappear after the standard is ratified and it is no longer a “proposal”. We are nearing the point where the committee is going to submit the draft of the standard for the ratification process, and there is a lot more interest being generated by early adopters, so there is a need for some explanation, understanding, and analysis concerning the costs, efficiencies, configurations and implementations of 1687 (also referred to as IJTAG, where the “I” means “internal”). This first blog answers the question, “what is IEEE 1687”, and subsequent blogs will cover the topics “who uses IEEE 1687”, “what are the advantages of using IEEE 1687 (why use IEEE 1687)”, and “how to use IEEE 1687.”