Transcript FEST - Purdue College of Engineering

FEST
ECE 477 Fall 2011
TEAM 5
Gloria Budiman
Alexander Kidarsa
Christopher Sakalis
Vishal Gala
FEST
 Far
 End
 Speakerphone
 Test
 System
INTRODUCTION
 Speakerphone quality testing
 Micro Controller
 Codec
 Muxes
 Capacitors
 etc
RELIABILITY ANALYSIS
 Voltage Regulator
• 2 voltage needed
• 3.3V
• 5V
• 2 boards -> 4 needed
• Gets really hot
 λp = λb x πT x πT x πS x πC x πQ x πE
= 0.002 x 3.7 x 3.7 x 1.0 x 1.0 x 1 x 6.0
= 0.16428
RELIABILITY ANALYSIS
 Micro Controller
•
•
•
•
Main brain of the whole system
Most complex chip
Most pins
Might get warm when doing a lot of computation
 λp = [C1 x πT + C2 x πE] x πQ x πL
= [0.56 x 0.35 + 0.32 x 2.0] x 10 x
= 8.36
RELIABILITY ANALYSIS
 Codec
•
•
•
•
Used to convert digital to analog
Used to convert analog to digital
Second most pin
Second most complicated chip
 λp = λBD x πMFG x πT x πCD + λBP x πE x πQ x πPT + λEOS
= 0.16 x 0.55 x 0.35 x 14 + 0.0027 x 2.0 x 10 x 4.7 + 0.65
= 1.335
RELIABILITY ANALYSIS
PARAMETER NAME
DESCRIPTION
VALUE
COMMENTS
Voltage Regulator
Gets really hot
0.16428
Some of the words are
barely readable.
Micro Controller Unit
Die Complexity
8.36
Codec
Die Complexity
1.335
Entire Design
9.85928
FMECA
FMECA
FMECA P1_PS1
Failure No.
Failure Mode
Possible
Causes
Failure
Effects
Method of
Detection
Criticality
PS-a
Output < 3.3V Voltage
or 5V
regulator
stopped
working
The device
will stop
working
Output
Low
voltage lower
than expected.
Device stops
working
PS- b
Output = 0
The device
will stop
working
Heartbeat
LED stops
blinking.
Capacitor
stopped
working
Low
Remarks
FMECA
FMECA P1_PERI1
Failure No.
PERI-a
PERI-b
PERI-c
PERI-d
Failure
Mode
Pressing
push button
doesn’t
navigate
through
menu
SD Card
detected but
no data
found
Unable to
run
initialize
test
LCD is
blank
Possible
Causes
Push button
failure
Failure
Effects
Unable to
start or stop
testing
modules.
Method of
Detection
Observation
Low
SD Card
board
broken
Unable to
read or
write to SD
Card
Unable to
initialize
SPL
Observation
Low
Observation
Low
Unable to
see and
navigate
menus
Observation
Low
RS232-Mux
failure
LCD failure
OR
RS232-Mux
failure
Criticality
Remarks
FMECA
FMECA P1_MCU1
Failure No.
Failure Mode
Possible
Causes
Failure
Effects
Method of
Detection
Criticality
MCU-a
System halt
MCU Failure,
Capacitor
failure
The device
stops working
Heartbeat
LED stops
blinking
Low
MCU-b
System
behaves
weirdly
Decoupling
Capacitor
failure
Dirty signals
received
might cause
the system to
behave
weirdly
System
behavior is
not as
expected
Low
Remarks
Not sure what
might
happened
FMECA
FMECA P2_PS1
Failure No.
Failure Mode
Possible
Causes
PS-a
Output < 3.3V Voltage
regulator
or 5V
stopped
working
PS- b
Output = 0
Capacitor
stopped
working
Failure
Effects
Method of
Detection
Criticality
The device will Output voltage Low
lower than
stop working
expected.
Device stops
working
The device will Heartbeat
LED stops
stop working
blinking.
Low
Remarks
FMECA
FMECA P2_AC1
Failure No.
Failure Mode
Possible
Causes
Codec failure,
Codec Mux
failure, MCU
failure
Failure
Effects
No sound can
be heard from
the speaker
Method of
Detection
Observation
Criticality
AC-a
No sound
from speaker
AC-b
Unable to
write data
Codec Failure,
Codec Mux
Failure, MCU
failure, Single
Ended to
Differential
Chip failure
No data can be Observation
written to the
SD card
Low
AC-c
Unable to
connect to
phone
CH1840
failure
Unable to dial
nor be dialed
Low
No dial tone,
observation
Low
Remarks
Cable failure
is a possibility
but not
regarded as
device failure
Telco system
failure a
possibility but
not regarded
as device
failure
SUMMARY
 Product should be pretty reliable
• Assuming correct usage
 Low Criticality
• The user should not be injured should the product fail
• Unless the user touches the voltage regulator directly as soon as the
device fails.
QUESTIONS(?_?)