Reliability Report

AOS Semiconductor
Product Reliability Report
AOB256L,
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 AOB256L. 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 AOB256L passes AOS quality and
reliability requirements. The released product will be categorized by the process family and be
monitored on a quarterly basis for continuously improving the product quality.
Table of Contents:
I.
II.
III.
IV.
Product Description
Package and Die information
Environmental Stress Test Summary and Result
Reliability Evaluation
I. Product Description:
The AOB256L uses trench MOSFET technology that is uniquely optimized to provide the most
efficient high frequency switching performance. Both conduction and switching power losses are
minimized due to an extremely low combination of RDS(ON), Ciss and Coss. This device is ideal for
boost converters and synchronous rectifiers for consumer, telecom, industrial power supplies and
LED backlighting.
-RoHS Compliant
-Halogen Free
Details refer to the datasheet.
II. Die / Package Information:
AOB256L
Standard sub-micron
150V N channel process
Package Type
TO263
Lead Frame
Bare Cu
Die Attach
Soft solder
Bonding
Al wire
Mold Material
Epoxy resin with silica filler
Moisture Level
Up to Level 1 *
Note * based on info provided by assembler and mold compound supplier
Process
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III. Result of Reliability Stress for AOB256L
Test Item
Test Condition
Time
Point
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
[email protected]°c
Temp = 150°c ,
Vgs=100% of
Vgsmax
-
Temp = 150°c ,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
HAST
130 , 85%RH,
33.3 psi, Vgs =
100% of Vgs max
100 hrs
Pressure Pot
121°c , 29.7psi,
RH=100%
96 hrs
Temperature
Cycle
-65°c to 150°c ,
air to air,
250 / 500
cycles
HTGB
HTRB
168hrs
500 hrs
1000 hrs
Lot
Attribution
Total
Sample size
Number
of
Failures
Reference
Standard
13 lots
2255pcs
0
JESD22A113
1 lot
308pcs
0
JESD22A108
77 pcs / lot
308pcs
0
JESD22A108
(Note A*)
6 lots
77 pcs / lot
330pcs
0
JESD22A110
(Note A*)
13 lots
55 pcs / lot
1001pcs
0
JESD22A102
(Note A*)
77 pcs / lot
0
JESD22A104
3 lots
(Note A*)
1 lot
3 lots
12 lots
(Note A*)
924pcs
77 pcs / lot
Note A: The reliability data presents total of available generic data up to the published date.
IV. Reliability Evaluation
FIT rate (per billion): 7
MTTF = 15704 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size of the selected product (AOB256L). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
2
9
9
Failure Rate = Chi x 10 / [2 (N) (H) (Af)] = 1.83 x 10
9
8
MTTF = 10 / FIT = 1.38 x 10 hrs = 15704 years
/ [2x (2x77x168+2x3x77x1000) x258] = 7
Chi² = Chi Squared Distribution, determined by the number of failures and confidence interval
N = Total Number of units from HTRB and HTGB tests
H = Duration of HTRB/HTGB 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:
55 deg C
70 deg C
85 deg C
100 deg C
115 deg C
Af
258
87
32
13
5.64
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
130 deg C
150 deg C
2.59
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