Reliability Report

AOS Semiconductor
Product Reliability Report
AOZ8251D,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
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This AOS product reliability report summarizes the qualification result for AOZ8251D.
Accelerated environmental tests are performed on a specific sample size, and then followed by
electrical test at end point. Review of final electrical test result confirms that AOZ8251D passes
AOS quality and reliability requirements. The released product will be categorized by the process
family and be routine monitored for continuously improving the product quality.
I. Reliability Stress Test Summary and Results
Test Item
Test Condition
Time
Point
Total
Sample
size
Number
of
Failures
Reference
Standard
HTRB
Temp = 150°C ,
Vds=80% of Vbrmax
168 / 500 /
1000 hours
924 pcs
0
JESD22-A108
-
1386 pcs
0
JESD22-A113
96 hours
462 pcs
0
JESD22-A110
Precondition
(Note A)
HAST
168hr 85°C/85%RH +
3 cycle reflow@260°C
(MSL 1)
130°C , 85%RH,
33.3 psi,
Vdd = 80% of Vbrmax
Autoclave
121°C , 29.7psia,
RH=100%
96 hours
462 pcs
0
JESD22-A102
Temperature
Cycle
-65°C to 150°C ,
air to air,
250 / 500
cycles
462 pcs
0
JESD22-A104
Note: The reliability data presents total of available generic data up to the published date.
Note A: MSL (Moisture Sensitivity Level) 1 based on J-STD-020
II. Reliability Evaluation
FIT rate (per billion): 6.10
MTTF = 18700 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size. Failure Rate Determination is based on JEDEC Standard JESD 85. FIT means one
failure per billion hours.
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Failure Rate = Chi x 10 / [2 (N) (H) (Af)] = 6.10
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MTTF = 10 / FIT = 18700 years
Chi²= Chi Squared Distribution, determined by the number of failures and confidence interval
N = Total Number of units from burn-in tests
H = Duration of burn-in testing
Af = Acceleration Factor from Test to Use Conditions (Ea = 0.7eV and Tuse = 55°C)
Acceleration Factor [Af] = Exp [Ea / k (1/Tj u – 1/Tj s)]
Acceleration Factor ratio list:
Af
55 deg C
70 deg C
85 deg C
100 deg C
115 deg C
130 deg C
150 deg C
259
87
32
13
5.64
2.59
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Tj s = Stressed junction temperature in degree (Kelvin), K = C+273.16
Tj u =The use junction temperature in degree (Kelvin), K = C+273.16
k = Boltzmann’s constant, 8.617164 X 10-5eV / K
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