4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Characterization of Single-Event Transients in the LM119 Voltage Comparator
S. Buchner, Radiation Effects and Analysis Group NASA/GSFCD. McMorrow, Naval Research Laboratory
R. Pease, RLP Research, M. Maher, National Semiconductor,
R. Koga, Aerospace CorpA. Sternberg and L. Massengill, Vanderbilt University
• NASA Electronic Parts and Packaging (NEPP) Program’s Electronic Radiation Characterization (ERC) Project
• DTRA RHM
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Outline
• Introduction
• Comparison of Pulsed-Laser Data, Modeling and Heavy-Ion Data– Dependence on Differential Input Voltage
– Negative vs Positive differential voltages
• Conclusions
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
SETs in Linear Circuits
• SETs are momentary disturbances in the output voltage following an ion strike to a sensitive node in a circuit.
• SETs have been observed in– Voltage comparators (LM111, LM119, LM139)– Operational amplifiers (LM124)– Hybrids such as DC to DC Converters (2812)
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
SETs in Linear Circuits
• Depend on Operating Conditions:– Power supply– Output load– Input voltages
• SET Characteristics:– Amplitude– Width– Threshold
R
Vdd
Vss
Vin(+)
Vin(-)LM119
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
LM119 Heavy Ion Data
• Testing under limited set of conditions - results may not be applicable to another application
10-7
10-6
10-5
10-4
10-3
0 20 40 60 80
? V=1.3 V? V=2.0 V? V=0.05 V
LET(MeV.cm2/mg)
SE
U C
ross
-sec
tion
(cm
2 )
Vdd=+15V, Vss=-15V
Koga et al.1997
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Characterization Approach
• To minimize costs of characterizing SET sensitivity of linear circuits, use a canonical set of data:– heavy-ion tests (Cross-section vs LET and transients waveforms)
– modeling (device and circuit simulator programs)
– ion microprobe (focused beam on known locations)
– pulsed laser (focused beam of light)
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
LM119 Circuit Diagram
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
LM119 Photomicrograph
EB C.
Q2
Laser Light
Substrate
B E COxide
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
SET Sensitive Region for Q6
E BC
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
SET Sensitive Region for Q10
E B E
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Pulsed-Laser Induced Transients
.
1
2
3
4
5
0 1x10-7 2x10-7 3x10-7
Q15Q10Q6Q3Q2Q11
Time (s)
Am
plitu
de (
V)
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Pulsed-Laser Induced Transients
.
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Comparison of Transistor Sensitivity to SEEs from Pulsed Laser Light and Modeling
Transistor Delta V > 0 Delta V < 0Laser Modeling Laser Modeling
Q1 Y Y Y YQ2 Y Y Y YQ3 Y Y Y YQ4 N N Y YQ5 N N N NQ6 Y Y N NQ7 N N Y YQ8 N Y Y YQ9 Y Y N YQ10 Y Y Y YQ11 Y Y Y YQ12 N Y Y YQ13 N N Y YQ14 Y Y N NQ15 Y Y Y YQ16 Y Y Y YQ17 Y Y Y YQ18 N N Y NQ19 N N N NQ20 Y Y Y YQ21 N Y Y YQ22 Y Y Y Y
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Pulsed Laser ResultsTransistor DeltaV=+60mV DeltaV=-60mV
Q1 1Q2 29 9Q3 22Q4 7Q6 18Q7 9Q8 7Q10 33 7Q11 16 4Q12 4Q15 11Q16 7Q17 4Q18 4Q20 4
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Heavy Ion Results
0.00001
0.0001
0.001
0.01
0 20 40 60
? V=- - 5? V=-1.0? V= - 0.2? V=4.5V? V=2.5 V? V=0.12V
Vdd=5VVss=-5VR=1.7 K?
LET (MeV.cm2/mg)
Cro
ss S
ectio
n (c
m2 )
LM119
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Pulsed Laser Results
0
1
2
3
4
5
0 1 2 3 4 5
Circuit SimulationPulsed Laser Data with Small QdepPulsed Laser Data With Large Qdep
Differential Input Voltage (V)
SE
T A
mpl
itude
(V
)
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Pulsed Laser Results
0
1
2
3
4
5
0 1 2 3 4 5
Differential Input Voltage (V)
SE
T A
mpl
itude
(V
)
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Heavy Ion Results
0.00001
0.0001
0.001
0 20 40 60
Vdd = 5V, ? V = 4.5VV
dd = 5V, ? V = 0.12V
LET (MeV.cm2/mg)
Cro
ss-S
ectio
n (c
m2 )
LM119
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Heavy Ion Results
0.00001
0.0001
0.001
0.01
0 20 40 60
? V=- - 5? V=-1.0? V= - 0.2? V=4.5V? V=2.5 V? V=0.12V
Vdd=5VVss=-5VR=1.7 K?
LET (MeV.cm2/mg)
Cro
ss S
ectio
n (c
m2 )
LM119
4/24/02SEE Symposium, Los Angeles, CA04/24/02 - presented by Stephen Buchner
Conclusions
• There is a wide parameter space for SETs in linears.
• Avoid heavy-ion testing for each condition by doing modeling.
• SPICE modeling requires a significant effort particularly if transistor parameters are not known.
• SET data from a pulsed laser can be used to validate SPICE models in a feedback mode.
• Ion microprobe is a valuable aid because of limitations of laser, i.e. metal coverage and penetration depth of the light.
• Pulsed laser can be used to check unique conditions rapidly.