Tutorial Links
Quality & Reliability General Guidelines
Reliability
- Life Test
- High Temp. High Humidity storage
- High Temp. High Humidity Bias/Operation
- Thermal Stress (TCT,TS)
- High Temp Storage/Bias/Operation
- Solder Shock / Reflow Test
- Mechanical
- Drop/Bending/Twist/Key Force/Partial Pressure
- ESD
- Latch Up, etc..
COB Evaluation System (example)
1 |
2 |
3 |
||
HAST |
200h |
100h |
--- |
121/100% |
85/85 |
1000h |
500h |
240h |
|
60/90 |
1000h |
500h |
240h |
|
Temp Cycle |
1000c |
200c |
100c |
-65 / 150 |
Operating life |
1000h |
240h |
120h |
Max operating temp |
Process Flow Design Issues
COB > SMT
- Solder Printing
- Thermal Stress
- Moisture Problem
- COB Component Distance Gap
SMT > COB
- PCB Cleaning
- Out gas Contamination
- Solder Joint Reliability at Curing Time
- ESD by Mounted Capacitance
- SMT Device Testing
COB & SMT or SMT & COB
COB & SMT |
SMT & COB |
|
PCB Contam |
OK |
(Flux, Out gas) |
PCB Cleaning |
OK |
? |
Reflow |
(Moisture, Temp) |
OK |
Solder Printing |
(Emboss Mask) |
OK |