Reliability Report

AOS Semiconductor
Product Reliability Report
AOT20C60,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
1
This AOS product reliability report summarizes the qualification result for AOT20C60. 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 AOT20C60 passes AOS quality
and reliability requirements.
Table of Contents:
I.
II.
III.
IV.
V.
Product Description
Package and Die information
Environmental Stress Test Summary and Result
Reliability Evaluation
Appendix: Test data
I. Product Description:
The AOT20C60 is fabricated using an advanced high voltage MOSFET process that is designed
to deliver high levels of performance and robustness in popular AC-DC applications. By providing
low RDS(on), Ciss and Crss along with guaranteed avalanche capability this parts can be
adopted quickly into new and existing offline power supply designs.
For Halogen Free add "L" suffix to part number:
AOT20C60L
Details refer to the datasheet.
II. Die / Package Information:
AOT20C60
Standard sub-micron
600V N-Channel MOSFET
Package Type
TO220
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
2
III. Result of Reliability Stress for AOT20C60
Test Item
Test Condition
Time
Point
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
reflow@250°c
Temp = 150°c ,
Vgs=100% of
Vgsmax
-
12 lots
168hrs
500 hrs
1000 hrs
3 lots
4 lots
Temp = 150°c ,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
3 lots
4 lots
77 pcs / lot
HAST
130°c , 85%RH,
33.3 psi, Vgs =
100% of Vgs max
96 hrs
9 lots
Pressure Pot
121°c , 29.7psi,
RH=100%
96 hrs
HTGB
HTRB
Temperature
Cycle
-65°c to 150°c ,
air to air,
250 / 500
cycles
Lot
Attribution
Total
Sample size
Number
of
Failures
Reference
Standard
2112pcs
0
JESD22A113
539pcs
0
JESD22A108
0
JESD22A108
495pcs
0
JESD22A110
(Note A*)
9 lots
55 pcs / lot
693pcs
0
JESD22A102
(Note A*)
77 pcs / lot
0
JESD22A104
77 pcs / lot
539pcs
12 lots
(Note A*)
924pcs
77 pcs / lot
IV. Reliability Evaluation
FIT rate (per billion): 4.16
MTTF = 27426 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size of the selected product (AOT20C60). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
2
9
Failure Rate (FIT) = Chi x 10 / [2 (N) (H) (Af)]
9
= 1.84 x 10 / [2x (6x77x500 +8x77x1000) x259] = 4.16
9
8
MTTF = 10 / FIT = 2.40 x 10 hrs = 27426 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
k = Boltzmann’s constant, 8.617164 x 10-5eV / K
130 deg C
150 deg C
2.59
1
3