Reliability Report

AOS Semiconductor
Product Reliability Report
AON7280,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
This AOS product reliability report summarizes the qualification result for AON7280.
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 AON7280
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 AON7280 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.
Detailed information refers to datasheet.
II. Die / Package Information:
AON7280
Standard sub-micron
80V N channel
Package Type
DFN 3.3x3.3
Lead Frame
Cu
Die Attach
Solder paste
Bonding
Cu clip
Mold Material
Epoxy resin with silica filler
MSL (moisture sensitive level) Level 1 based on J-STD-020
Process
Note * based on information provided by assembler and mold compound supplier
III. Result of Reliability Stress for AON7280
Test Item
Test Condition
Time
Point
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
reflow@260°c
-
HTGB
Temp = 150 °c,
Vgs=100% of
Vgsmax
168hrs
500 hrs
1000 hrs
Temp = 150 °c,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
HAST
130 °c, 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
HTRB
Lot
Attribution
Total
Sample
size
Number
of
Failures
Standard
11 lots
2299pcs
0
JESD22A113
1 lot
308pcs
0
JESD22A108
77pcs / lot
308pcs
0
JESD22A108
(Note A*)
11 lots
77pcs / lot
605pcs
0
JESD22A110
(Note A*)
11 lots
55pcs / lot
847pcs
0
JESD22A102
(Note A*)
11 lots
77pcs / lot
847pcs
0
JESD22A104
(Note A*)
77pcs / lot
3 lots
(Note A*)
1 lot
3 lots
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 (AON7280). Failure Rate Determination is based
on JEDEC Standard JESD 85. FIT means one failure per billion hours.
2
9
Failure Rate = Chi x 10 / [2 (N) (H) (Af)]
9
= 1.83 x 10 / [2x (2x77x168+6x77x1000) x258] = 7
9
8
MTTF = 10 / FIT = 1.38 x 10 hrs = 15704 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
-5
K = Boltzmann’s constant, 8.617164 X 10 eV / K