AOS Semiconductor Product Reliability Report

AOS Semiconductor
Product Reliability Report
AON6912L
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
495 Mercury Drive
Sunnyvale, CA 94085
U.S.
Tel: (408) 830-9742
www.aosmd.com
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This AOS product reliability report summarizes the qualification result for AON6912L. 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 AON6912L 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.
V.
Product Description
Package and Die information
Environmental Stress Test Summary and Result
Reliability Evaluation
Quality Assurance Information
I. Product Description:
The AON6912L is designed to provide a high efficiency synchronous buck power stage with
optimal layout and board space utilization. It includes two specialized MOSFETs in a dual Power
DFN6x5 package. The Q1 "High Side" MOSEFT is designed to minimize switching losses. The
Q2 "Low Side" MOSFET is an low RDS(ON) to reduce conduction losses. The AON6912L is well
suited for use in compact dc/dc converter applications.
-RoHs Compliant
-Halogen Free
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II. Die / Package Information:
AON6912L
Standard sub-micron
Low voltage N channel process
8 leads DFN 5×6A
A194, Ag spot
Silver epoxy
Au 2mils
Epoxy resin with silica filler
UL-94 V-0
Up to Level 1 *
Process
Package Type
Lead Frame
Die Attach
Bond wire
Mold Material
Flammability Rating
Moisture Level
Note * based on info provided by assembler and mold compound supplier
III. Result of Reliability Stress for AON6912L
Test Item
Test Condition
Time
Point
Solder
Reflow
Precondition
168hr 85°°c /85%RH +3
cycle reflow @260°°c
-
HTGB
Temp = 150°°c ,
Vgs=100% of Vgsmax
168hrs
500 hrs
1000 hrs
Lot Attribution
2 lots
Total
Sample
size
Number
of
Failures
275 pcs
0
77 pcs
0
(Note B**)
1 lot
(Note A*)
77 pcs / lot
Temp = 150°°c ,
Vds=80% of Vdsmax
168hrs
500 hrs
1000 hrs
HAST
130 +/- 2°°c , 85%RH,
33.3 psi, Vgs = 80% of
Vgs max
100 hrs
1 lot
55 pcs
0
Pressure Pot
121°°c , 29.7psi,
RH=100%
96 hrs
2 lots
55 pcs / lot
110 pcs
0
Temperature
Cycle
-65°°c to 150°°c ,
air to air
250 / 500
cycles
2 lots
55 pcs / lot
110 pcs
0
HTRB
77 pcs
0
1 lot
(Note A*)
77 pcs / lot
55 pcs / lot
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III. Result of Reliability Stress for AON6912L
Continues
DPA
Internal Vision
Cross-section
X-ray
CSAM
NA
5
5
5
5
5
5
0
NA
5
5
0
Bond Integrity
Room Temp
150°°c bake
150°°c bake
0hr
250hr
500hr
40
40
40
40 wires
40 wires
40 wires
0
Solderability
245°°c
5 sec
15
15 leads
0
Note A: The HTGB and HTRB reliability data presents total of available AON6912L burn-in data
up to the published date.
IV. Reliability Evaluation
FIT rate (per billion): 46
MTTF = 2478 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size of the selected product (AON6912L). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
Failure Rate = Chi2 x 109 / [2 (N) (H) (Af)] = 1.83 x 109 / [2x2x77x500x258] = 46
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MTTF = 10 / FIT = 2.17 x 10 hrs = 2478 years
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:
Af
55 deg C
70 deg C
85 deg C
100 deg C
115 deg C
130 deg C
150 deg C
258
87
32
13
5.64
2.59
1
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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