Reliability Report

AOS Semiconductor
Product Reliability Report
AON6922,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
This AOS product reliability report summarizes the qualification result for AON6922.
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 AON6922
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 AON6922 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 DFN5x6A package. The Q1 "High Side" MOSFET is designed to minimize switching
losses. The Q2 "Low Side" MOSFET is designed for low RDS(ON) to reduce conduction losses.
The AON6922 is well suited for use in compact DC/DC converter applications.
-RoHS Compliant
- Halogen Free
Detailed information refers to datasheet.
II. Die / Package Information:
AON6922
Standard sub-micron
Low voltage N channel
Package Type
DFN 5x6A
Lead Frame
Copper
Die Attach
Solder paste
Bonding Wire
N.A for clip bond
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 AON6922
Test Item
Test Condition
Time
Point
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
[email protected]°c
HTGB
HTRB
HAST
Pressure Pot
Temperature
Cycle
Lot
Attribution
Total
Sample
size
Number
of
Failures
Standard
-
11 lots
1815pcs
0
JESD22A113
Temp = 150 °c,
Vgs=100% of
Vgsmax
168hrs
500 hrs
1000 hrs
1 lot
308pcs
0
JESD22A108
Temp = 150 °c,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
77pcs / lot
308pcs
0
JESD22A108
130 +/- 2°°c,
85%RH, 33.3 psi,
Vgs = 80% of Vgs
max
121°°c, 29.7psi,
RH=100%
100 hrs
(Note A*)
11 lots
77pcs / lot
605pcs
0
JESD22A110
96 hrs
(Note A*)
11 lots
55pcs / lot
605pcs
0
JESD22A102
-65°°c to 150°°c,
air to air
250 / 500
cycles
(Note A*)
11 lots
55pcs / lot
605pcs
0
JESD22A104
(Note A*)
55pcs / 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 (AON6922). 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 (2xx77x168+2x3x77x1000) 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