Reliability Report

AOS Semiconductor
Product Reliability Report
AON7296,
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
This AOS product reliability report summarizes the qualification result for AON7296.
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 AON7296
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 AON7296 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:
AON7296
Standard sub-micron
100V N channel MOSFET
Package Type
DFN 3x3 EP
Lead Frame
Cu Alloy
Die Attach
Ag epoxy
Bonding
Cu wire
Mold Material
Epoxy resin with silica filler
MSL (moisture sensitive level) Level 1 based on J-STD-020
Process
III. Result of Reliability Stress for AON7296
Test Item
Test Condition
Time
Point
Lot
Attribution
Total
Sample
size
Number
of
Failures
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
reflow@260°c
HTGB
Standard
-
12 lots
2618pcs
0
JESD22A113
Temp = 150 c,
Vgs=100% of
Vgsmax
168hrs
500 hrs
1000 hrs
2 lots
4 lots
3 lots
693pcs
0
JESD22A108
HTRB
Temp = 150 c,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
(Note A*)
2 lots
4 lots
3 lots
77 pcs / lot
693pcs
0
JESD22A108
HAST
130 c, 85%RH,
33.3 psi, Vgs =
100% of Vgs max
96 hrs
(Note A*)
11 lots
77 pcs / lot
847pcs
0
JESD22A110
Pressure Pot
121c, 29.7psi,
RH=100%
96 hrs
(Note A*)
11 lots
77pcs / lot
847pcs
0
JESD22A102
Temperature
Cycle
-65c to 150c,
air to air
250 / 500
cycles
(Note A*)
12 lots
77pcs / lot
924pcs
0
JESD22A104
(Note A*)
77pcs / lot
Note A: The reliability data presents total of available generic data up to the published date.
IV. Reliability Evaluation
FIT rate (per billion): 4.29
MTTF = 26608 years
The presentation of FIT rate for the individual product reliability is restricted by the actual
burn-in sample size of the selected product (AON7296). 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 (4x77x168+8x77x500+6x77x1000) x259] = 4.29
9
8
MTTF = 10 / FIT = 2.33 x 10 hrs = 26608 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
259
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