VISHAY EPICXXXGW

EPIC
Vishay Sfernice
Electro-Pyrotechnic Initiator Chip Resistor
FEATURES
Vishay has developed a special thin film resistor
chip specifically designed to provide pyrotechnic
engineers with a lot of advantages
• Firing energy down to 50 µJ
Pb-free
Available
RoHS*
COMPLIANT
• Firing time down to 50 µs
Electro-pyrotechnic initiator resistors, also known as bridge
resistors, are resistive elements, which convert electrical
energy into heat energy in a precise electro-thermal profile
for the purpose of initiating a series of pyrotechnic events in
a controlled energetic reaction. In automotive applications
this effect is used to deploy automotive airbags and other
safety devices. These same devices are also used in military
applications for pilot ejection systems, explosive bolt
disengagement of airbone missiles, chaff dispensers,
artillery projectile activators, anti-tank mines, etc.
Commercially, they are used in mining and de-constructions
applications.
• Ohmic range: 2R to 10R
• Compatibility with various pyrotechnic composition even
with no primer
• Joule effect ignition or flash ignition for very fast firing
• Easy set up by design of firing levels
• “No fire”/“all fire” ratio up to 70 %
• Very predictable, reproducible and reliable behaviour
• Size: 0603 preferred - other size available upon request
PRINCIPLE OF OPERATION
The two main parameters of an EPIC are “no fire” and “all
fire” conditions.
“No fire” represents the immunity of the resistor to the
environmental electro-magnetic pollution and electric
continuity test: Therefore customer will have to provide
Vishay/Sfernice with “no firing” conditions: Maximum current
and longest duration when part should not ignite the
explosive powder.
“All fire” represents the command pulse. Customer will have
to provide Vishay/Sfernice with “all firing” conditions:
Minimum current, duration necessary to ignite the explosive
powder.
DIMENSIONS in millimeters (inches)
A
B
C
DIMENSION
CASE
SIZE
0603
A
B
C
MAX. TOL. + 0.152 (0.006)
MIN. TOL. - 0.152 (0.006)
MAX. TOL. + 0.127 (0.005)
MIN. TOL. - 0.127 (0.005)
MAX. TOL. + 0.127 (0.005)
MIN. TOL. - 0.127 (0.005)
1.52 (0.060)
0.75 (0.030)
0.5 (0.020)
MECHANICAL SPECIFICATIONS
• Substrate: Special alumina based substrate
• Resistive element: Fine line patterned Tantalum nitride thin
film layer
• Diffusion and conductive thin film layers
• Terminations: Wraparound over nickel barrier
TECHNOLOGY
This technology contributes to the stability of the heating element, the precise electro-thermal response profile and the ability to
design a precise activation energy.
All these features are perfectly controlled on high production volumes.
* Pb containing terminations are not RoHS compliant, exemptions may apply
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For technical questions, contact: [email protected]
Document Number: 53041
Revision: 03-Nov-08
EPIC
Electro-Pyrotechnic Initiator Chip Resistor
Vishay Sfernice
EXAMPLE OF APPLICATION
Chip: 0603
R: 2R ± 0R2
Energy: Around 1.5 mJ
Response time: 0.2 ms
Mounting Recommendations
EPIC can be mounted either on a PCB or on a squib. Please refer to Application Note (http://www.vishay.com//doc?53044) to
see Vishay/Sfernice recommendations.
AIRBAGS INITIATORS
A prerequisite to valid reliability estimation of an electro-explosive device (EED) is a sensitivity test program carefully chosen and
properly perform. The Bruceton Method (or up and down method) of sensitivity testing was developed specifically for ordinance
testing. Here under is an example of Bruceton’s test results.
2 customers: Customer A and customer B have equipped squibs of their own with 3 variants (Variant 1, 2 and 3) . Bruceton’s test
results of Vishay heating elements are shown in Table 1
CUSTOMER A
HEATING ELEMENT
CUSTOMER B
NF (in mA)
AF (in mA)
NF (in mA)
AF (in mA)
Variant 1
546
766
538
776
Variant 2
571
839
577
859
Variant 3
619
891
612
875
CONCLUSION
Bruceton test results are self explanatory. They show that the electro-thermal behavior of EPIC is predictable, precise and
reproducible.
For more information please read the Application Note (http://www.vishay.com/doc?53044).
HOW TO GET THE RIGHT EPIC
Each EPIC will have to be adapted to customer pyrotechnic element. To reach the right product, Vishay/Sfernice works by
“iteration”. Upon receipt of the EPIC Design Guide (http://www.vishay.com/doc?53045) duly filled, an initial sampling lot is given
to customer (along with an EPIC reference) so he can provide Vishay/Sfernice with “no firing”/“all firing” conditions.
Then Vishay/Sfernice will be able to provide a new set of samples (eventually tooling charges will be necessary). Ohmic value of
samples will remain the same, but there will be a new compromise between the length, the width and the thickness of the filament
so as to increase the sensitivity of the EPIC and adapt the firing conditions to the pyrotechnic element of the customer.
When the right parameters are reached Vishay/Sfernice will design a final set of mask (with the participation of the customer).
ORDERING PROCEDURE
New Global Part Numbering: EPICxxxxNT
E
P
I
C
x
x
x
x
N
T
MODEL
xxxx
TERMINATION (1)
PACKAGING
EPIC
Will be determined
at time of design
N: Tin/silver
B: Tin/lead
G: Gold
W = Waffle pack
T = Tape and reel
Notes
(1) Tin/lead: Please consult
• EPIC being a semi-custom product, please fill EPIC Design Guide (http://www.vishay.com/doc?53045) and send to
[email protected] to get appropriate part number.
• Per Vishay policy all the components designed for automotive applications should be tested in accordance to AEC Q200
specification. As the EPIC is just part of an ignitor which is designed and qualified by each customer Vishay is not proceeding
to any AEC Q200 test.
Document Number: 53041
Revision: 03-Nov-08
For technical questions, contact: [email protected]
www.vishay.com
75
Legal Disclaimer Notice
Vishay
Disclaimer
All product specifications and data are subject to change without notice.
Vishay Intertechnology, Inc., its affiliates, agents, and employees, and all persons acting on its or their behalf
(collectively, “Vishay”), disclaim any and all liability for any errors, inaccuracies or incompleteness contained herein
or in any other disclosure relating to any product.
Vishay disclaims any and all liability arising out of the use or application of any product described herein or of any
information provided herein to the maximum extent permitted by law. The product specifications do not expand or
otherwise modify Vishay’s terms and conditions of purchase, including but not limited to the warranty expressed
therein, which apply to these products.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this
document or by any conduct of Vishay.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications unless
otherwise expressly indicated. Customers using or selling Vishay products not expressly indicated for use in such
applications do so entirely at their own risk and agree to fully indemnify Vishay for any damages arising or resulting
from such use or sale. Please contact authorized Vishay personnel to obtain written terms and conditions regarding
products designed for such applications.
Product names and markings noted herein may be trademarks of their respective owners.
Document Number: 91000
Revision: 18-Jul-08
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