Reliability Report

AOS Semiconductor
Product Reliability Report
AON7534,
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
This AOS product reliability report summarizes the qualification result for AON7534.
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 AON7534
passes AOS quality and reliability requirements.
Table of Contents:
I.
II.
III.
IV.
Product Description
Package and Die information
Environmental Stress Test Summary and Result
Reliability Evaluation
I. Product Description:
General Description
• Latest Trench Power AlphaMOS (α MOS LV) technology
• Very Low RDS(on) at 4.5VGS
• Low Gate Charge
• High Current Capability
• RoHS and Halogen-Free Compliant
Application
• DC/DC Converters in Computing, Servers, and POL
• Isolated DC/DC Converters in Telecom and Industrial
Detailed information refers to datasheet.
II. Die / Package Information:
AON7534
Standard sub-micron
Low voltage N channel
Package Type
DFN 3x3 EP
Lead Frame
Cu
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 AON7534
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
500hrs
1000 hrs
3 lots
3 lots
6 lots
924pcs
0
JESD22A108
HTRB
Temp = 150 c,
Vds=80% of
Vdsmax
168hrs
500hrs
1000 hrs
(Note A*)
3 lots
3 lots
6 lots
77pcs / lot
924pcs
0
JESD22A108
HAST
130c, 85%RH,
33.3 psi, Vds =
80% of Vdsmax
96 hrs
(Note A*)
11 lots
77pcs / 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): 2.86
MTTF = 39912 years
The presentation of FIT rate for the individual product reliability is restricted by the actual
burn-in sample size of the selected product (AON7534). 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 (6x77x168+ 6x77x500+ 12x77x1000) x259] = 2.86
9
8
MTTF = 10 / FIT = 3.50 x 10 hrs = 39912 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:
55 deg C
70 deg C
85 deg C
100 deg C
115 deg C
Af
259
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
-5
K = Boltzmann’s constant, 8.617164 X 10 eV / K
130 deg C
150 deg C
2.59
1