Conclusion:

32 TSOP 8mm

The following qualification successfully meets the quality and reliability standards required of all Dallas

Semiconductor packages:

Package Description:

A description of this assembly can be found in the product data sheet. You can find the product data

sheet at http://dbserv.maxim-ic.com/l_datasheet3.cfm.

Reliability Derating:

The Arrhenius model will be used to determine the acceleration factor for failure mechanisms that

are temperature accelerated.

AfT = exp((Ea/k)*(1/Tu - 1/Ts)) = tu/ts

AfT = Acceleration factor due to Temperature

tu = Time at use temperature (e.g. 55°C)

ts = Time at stress temperature (e.g. 125°C)

k = Boltzmann’s Constant (8.617 x 10-5 eV/°K)

Tu = Temperature at Use (°K)

Ts = Temperature at Stress (°K)

Ea = Activation Energy (e.g. 0.7 ev)

The activation energy of the failure mechanism is derived from either internal studies or industry

accepted standards, or activation energy of 0.7ev will be used whenever actual failure mechanisms

or their activation energies are unknown. All deratings will be done from the stress ambient

temperature to the use ambient temperature.

An exponential model will be used to determine the acceleration factor for failure mechanisms,

which are voltage accelerated.

AfV = exp(B*(Vs - Vu))

AfV = Acceleration factor due to Voltage

Vs = Stress Voltage (e.g. 7.0 volts)

Vu = Maximum Operating Voltage (e.g. 5.5 volts)

B = Constant related to failure mechanism type (e.g. 1.0, 2.4, 2.7, etc.)

The Constant, B, related to the failure mechanism is derived from either internal studies or industry

accepted standards, or a B of 1.0 will be used whenever actual failure mechanisms or their B are

unknown. All deratings will be done from the stress voltage to the maximum operating voltage.

Failure rate data from the operating life test is reported using a Chi-Squared statistical model at the

60% or 90% confidence level (Cf).

In addition, Dallas Semiconductor's continuous reliability monitor program ensures that all outgoing

assemblies will continue to meet Maxim's quality and reliability standards. The current status of the

reliability monitor program can be viewed at http://www.maxim-ic.com/TechSupport /dsreliability.html.

The failure rate, Fr, is related to the acceleration during life test by:

Fr = X/(ts * AfV * AfT * N * 2)

X = Chi-Sq statistical upper limit

N = Life test sample size