Reliability Report

AOS Semiconductor
Product Reliability Report
AO4840/L,
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
This AOS product reliability report summarizes the qualification result for AO4840/L.
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 AO4840/L
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 AO4840/L uses advanced trench technology MOSFETs to provide excellent RDS(ON) and
low gate charge. This dual device is suitable for use as a load switch or in PWM applications.
-RoHS Compliant
-AO4840L is Halogen Free
Detailed information refers to datasheet.
II. Die / Package Information:
AO4840/L
Standard sub-micron
Low voltage N channel, dual die
Package Type
8 lead SOIC
Lead Frame
Copper
Die Attach
Ag Epoxy
Bonding Wire
Au & Cu wire
Mold Material
Epoxy resin with silica filler
Flammability Rating
UL-94 V-0
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 AO4840/L
Test Item
Test Condition
Time
Point
Lot
Attribution
Total
Sample
size
Number
of
Failures
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
[email protected]°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
29 lots
3575pcs
0
JESD22A113
231pcs
0
JESD22A108
77pcs / lot
231pcs
0
JESD22A108
3 lots
130 +/- 2°°c,
85%RH, 33.3 psi,
Vgs = 80% of Vgs
max
121°°c, 29.7psi,
RH=100%
100 hrs
(Note A*)
16 lots
77pcs / lot
880pcs
0
JESD22A110
96 hrs
(Note A*)
20 lots
55 pcs / lot
1100pcs
0
JESD22A102
-65°°c to 150°°c,
air to air
250 / 500
cycles
(Note A*)
29 lots
55 pcs / lot
1595pcs
0
JESD22A104
(Note A*)
55 pcs / lot
3 lots
(Note A*)
HTRB
HAST
Pressure Pot
Temperature
Cycle
Standard
Note A: The reliability data presents total of available generic data up to the published date.
IV. Reliability Evaluation
FIT rate (per billion): 8
MTTF = 14871 years
The presentation of FIT rate for the individual product reliability is restricted by the actual
burn-in sample size of the selected product (AO4840/L). Failure Rate Determination is based
on JEDEC Standard JESD 85. FIT means one failure per billion hours.
2
9
9
Failure Rate = Chi x 10 / [2 (N) (H) (Af)] = 1.83 x 10
9
8
MTTF = 10 / FIT = 1.30 x 10 hrs = 14871 years
/ [2x6x77x1000x258] = 8
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
K = Boltzmann’s constant, 8.617164 X 10-5eV / K