Why Choose DES for HALT?

• We have vast expertise in HALT/HASS methods.
• We have performed an extensive amount of HALT tests on a variety of products.
• We have experience performing HALT from the circuit board level to the complex system level.
• Our vast experience will help you through the entire HALT process.
• We have many types of existing fixtures that we use at no charge our customers.
• We are experts at designing and making special custom fixtures.

Why Choose DES for HASS?

• We have experience working on many HASS projects.
• Manufacturers are currently subcontracting their HASS to DES with great success.
• We are capable of handling high volume projects.
• It may be more economical and efficient for DES to perform your HASS since we already have the specialized equipment and facilities in place.
• We can develop and manage the entire HASS process form Safety of Screen into production.
• We can provide total process and data management in production. We will conform to your quality and reporting requirements including supplying pass/fail certificates with every product.
• We are experts at designing and making production HASS fixtures.

Let DES Reduce Your Stress!

• HALT/HASS testing will find your product's weaknesses.
• The proper use of HALT can save $$$, reduce stresses, improve reliability, speed time to market, improve customer satisfaction, gain market share, and increase profits.
• HASS is a very cost effective way to find manufacturing defects, problems, and monitor processes.
• The proper use of HASS can reduce screening costs, improve process control and overall quality.
• DES will help you through the whole HALT/HASS process; find and analyze your high stress or weak areas; optimize your product stresses resulting in a rugged and reliable products.
• We don't just run the test, we offer SOLUTIONS!

Our 30 Cubic Foot HALT/HASS Chamber Can Apply:

CHART REAL30
HALT/HASS Chamber

• Temperatures from -100°C to +200°C (-148°F to +392°F).
• Temperatures can be raised or lowered up to 60°C (140°F) per minute.
• Vibration input levels up to 60 Grms with six degrees of freedom.
• Additional loads such as electrical, fluid pressure, etc. can be applied to parts inside the chamber simultaneously with temperature and vibration.

By using many different loads and combinations of loads, we can precipitate failures in our test chamber uncovering design or manufacturing process flaws before they reach your customer!

DES Will Guide You Through the Entire
HALT/HASS Process!

HALT at DES

An experienced DES engineer will help you through the HALT process. We will first analyze your product to identify potential weak areas. Then we will customize the HALT process to fit your particular application. At test completion, we will analyze your results and use our extensive material stress knowledge to recommend solutions. Finally, DES will prepare a thorough report, including test data, pictures, and the HALT results.

After completing HALT, DES will develop a HASS specifically for your product. A Proof of HASS procedure will be run to determine the screen's effectiveness in finding manufacturing flaws and to ensure that the screen does not remove significant life from the product. DES will run the HASS on your entire production or as an audit (HASA). DES will track and report the history of the results including all failure occurrences. In many cases we can complete the HASS process more efficiently and less expensive than setting up a HASS in-house.

We test many different kinds of electronic and electro-mechanical components in industries such as telecommunication, aerospace, medical, and consumer products. All of our instrumentation is maintained and calibrated traceable to NIST standards.

What is HALT?

HALT - Highly Accelerated Life Testing

HALT is used to find product design weaknesses making the product more rugged.

• HALT is done during the design process.
• Stresses are applied in steps to find a product's weaknesses, operational design margins, and destruct limits.
• Stresses are higher than normal to obtain time compression and accelerate aging.
• HALT is not a pass/fail test. It is pro-active! The stresses are increased until the product fails, rather than testing to predefined limits.
• All HALT failures represent an opportunitiy for improvement and will probably show up in the field.
• Many failures are easy and inexpensive to fix.
• HALT typically takes 3-5 days.

What is HASS?

HASS - Highly Accelerated Stress Screening

HASS is used to find defects and flaws in production to monitor the quality and consistency of your manufacturing processes.

• HASS testing is done during the production process.
• HASS is a screening method used to precipitate and find defects thus exposing manufacturing process problems that would cause a failure in normal field environments including shipping, storage and use.
• Stresses may be higher than normal operation to precipitate defects in a short amount of time. HASS stresses are typically higher than traditional Environmental Stress Screening (ESS).
• Types of stresses used are similar to those used in HALT.
• HASS screens take typically from a half hour to a few hours.
• HALT must be performed before HASS.
• Safety of Screen (SOS) is used to validate the screen proving that sufficient life is left for a normal use lifetime.

Reasons to Use HALT/HASS

• To produce a rugged, reliable product.
• Products have many electronic parts subjected to combined high/low temperature and vibration loads. Many parts are not tested for these combined loads.
• With thousands of electronic components present, a failure of a single component could cause the entire system to fail. This will lead to warranty and engineering redesign costs, and unhappy customers.
• To find and understand the operating limits of your parts.
• To find and understand the destruct limits of your parts.
• To compare different electronic components and suppliers (Evaluation of Competing Vendors).
• To regularly audit or screen your production components to check for and improve manufacturing quality.

Typical Stresses Used in HALT and HASS Testing

• Vibration applied over a broad frequency range
  (6 DOF, 60Grms, Random vibration energy to 10,000 Hz)
• Temperatures (-100°C to +200°C)
• High temperature rate of change (60°C / minute)
• Electrical loads
• More stresses (fluid pressure and viscosity, pH, unbalance, geometry, etc.)
• Combination of all loads

Typical HALT Profile

Typical HASS Profile

Why Products Fail

Stress vs. Strength

Every product has a statistical strength distribution. Failures will occur where the Product Strength and Field Stress Curves overlap. HALT/HASS will force the weaker components to fail in the chamber. HALT and HASS will shift the Product Strength curve to the right. The goal of HALT/HASS is to produce a large design margin or gap between the 2 curves, resulting in less field failures and a more reliable product!

Benefits of HALT

HALT of an Electronic
Chassis

• Shorter design cycle = Quicker Time to Market. Reduced design cost.
• Usually less expensive, faster, and more effective than traditional pass/fail testing.
• Find and improve design margins.
• Produce a more rugged/reliable product with less field failures and warranty expenses.
• Reliable products lead to happy customers.
• Happy customers lead to increased profits/market share.
• ROI's in the thousands or greater are being reported.

Benefits of HASS

• HASS screens are shorter than traditional methods (ESS).
• Reduced time and cost to screen production.
• Finds defects sooner and correct problems faster.
• Fewer defects reach the customers hands.
• Improved product quality and manufacturing process control.