Stress

Stress information for components is used during reliability predictions. RAM Commander Import wizard allows importing multiple types of actual stress values.

There are two possibilities for stress import in Import Wizard:

•	If it is constructed of semicolon-delimited abbreviation=value pairs like "TJC=5;VSR=0.4;" - use field “Stress Information” in “Operating” group.

•	If each stress (like VSR, PSR etc.) is located in its own separated field in the import file, select field names from the “Operating” group according to stress type.

After successful import you will see imported stress parameters on each component reliability prediction method data screen:

Note: Stress information is imported and taken into consideration only if all the conditions below are true:

a. Default reliability prediction method was defined for the project (see Project Configuration )

b. Load from Library is selected on the last Import Wizard step (see Step 4/5 - Finish )

c. Load from library for part was successful (part was found in library/automatic PN recognition etc.)

See the table of available stress types and their abbreviations in the table below:

Abbreviation	Description
CAP	Applied current
CSR	Current stress ratio (CSR)
PDI	Power dissipation
PSR	Power stress ratio (PSR)
TJC	Delta temperature junction to case (ambient)
VAA	Applied voltage (alternative)
VAP	Applied voltage (direct)
VDA	Applied voltage drain source
VDS	Voltage stress ratio drain source (VSRds)
VGA	Applied voltage gate source
VGS	Voltage stress ratio gate source (VSRgs)
VSR	Voltage stress ratio (VSR)
VRA	Rated Voltage
VGR	Rated Voltage gate source
VDR	Rated Voltage drain source
CRA	Rated Current
PRA	Rated Power
FRA	Frequency Applied
FRS	Frequency SR

Each component type (Item type) has its specific list of stress types it could have.

See the matrix below for the list of all Item types and their relevant stresses (split into two tables):

Part I (IC memory - Hf transistor)

Stress parameters

IC memory

IC analog

IC digital

Resistor

Poten-tiometer

Capacitor

Switch

Relay

Lf diode

Lf transistor

Hf diode

Hf transistor

Stress parameters

TJC

PDI

PSR

VSR

VAP

VAA

VGS

VGA

VDS

VDA

CSR

CAP

FRA

FRS

VRA

VGR

VDR

CRA

PRA

Stress para-meters

IC memory

IC analog

IC digital

Resis-tor

Poten-tiometer

Capa-citor

Switch

Relay

Lf diode

Lf transistor

Hf diode

Hf transistor

Stress parameters

Part II (Optoelectronic - Breaker)

Stress parameters	Optoelectronic	Bubble memory	Connector	Indu ctive	Fuse	Laser Diode	SAW	Lamp	Filter	Breaker	Stress parameters
TJC	+	+				+					TJC
PDI	+	+				+	+				PDI
PSR	+	+				+	+				PSR
VSR	+		-	+	+			+	+		VSR
VAP	+			+	+			+	+		VAP
VAA											VAA
VGS			+								VGS
VGA			+								VGA
VDS											VDS
VDA											VDA
CSR	+		+	+	+			+	+	+	CSR
CAP	+		+	+	+			+	+	+	CAP
FRA											FRA
FRS											FRS
VRA	+										VRA
VGR											VGR
VDR											VDR
CRA											CRA
PRA											PRA
Stress parameters	Opto-electronic	Bubble memory	Conn- ector	Indu ctive	Fuse	Laser Diode	SAW	Lamp	Filter	Breaker	Stress parameters