View detail for 3-lead CONTACT Package Usage

APPLICATION NOTE
3-lead CONTACT Package Usage
ATSHA204A, ATECC108A, and ATECC508A
Introduction
®
The Atmel CryptoAuthentication™ devices are often used in product accessory or
product ecosystem management. These include battery authentication or similar
applications where electrical contact with the authentication device is made using
mechanical pressure against compression connectors, i.e. unsoldered
connections.
This application note provides general usage guidelines for the 3-lead CONTACT
package option that is available with the Atmel symmetric and asymmetric
authentication products: ATSHA204A, ATECC108A, and ATECC508A.
3-lead CONTACT Package
 Intended for Use With Removable Accessories, Modules, or Components
 Electrical Contact Between IC and Host System is Accomplished With
Mechanical Pressure Contacts to Allow for Accessory Removal
 Use With Common Compression Connectors
Figure 1.
CONTACT Package Pinout
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
1
Package Substrate Support
The 3-lead CONTACT package is intended to be permanently attached to a base substrate (circuit board, frame,
system enclosure, etc.) to provide mechanical support for the IC as pressure is applied to make the electrical
contact.
The embossed/recessed IC receptacle shown in the below figure is an example and is not a required
configuration, but illustrates the need for proper mechanical support for the IC to ensure reliable long-term
operation under repeated pressure connection cycles.
Figure 1-1.
2
Embossed/Recessed IC Receptacle Example
Attachment of Package to Substrate
Attachment of the IC to the substrate itself can be accomplished with most standard epoxies or adhesives
depending on the mechanical and environmental requirements of the system in which it is used. The adhesive
should be applied in a pattern that will spread evenly along the package surface and will not leave large voids. An
approximate example is shown below:
Figure 2-1.
2
Adhesive Attachment
3-lead
CONTACT Package Usage [APPLICATION NOTE]
2
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
The amount of adhesive deposited depends upon the properties of the adhesive used, and the relevant
application notes of the adhesive supplier should be referenced. To provide even coverage of the rear surface of
3
the package to a uniform depth of 0.2mm will require the application of ~3mm of adhesive. Proper deposition of
adhesive should produce even distribution beneath the package with no voids as illustrated below:
Figure 2-2.
CORRECT – Even Adhesive Coverage
Compression Connector
3-lead CONTACT Device
Adhesive
If the deposition profile/pattern does not produce an even spread of adhesive, voids in the adhesive can result in
stress on the package when under pressure with the compression connector. The below figure illustrates an
example:
Figure 2-3.
INCORRECT – Uneven Adhesive Coverage Causing Voids
Compression Connector
3-lead CONTACT Device
Adhesive
3
Compression Connectors
The 3-lead CONTACT package is intended to be used with 2mm pitch compression connectors. The connectors
listed below or those with similar dimensions and mechanical characteristics can be used with this package:

Molex 47615-020

Molex 105040-001

Molex 47275-001
3-lead CONTACT Package Usage [APPLICATION NOTE]
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
3 3
Appendix A Package Drawing
A.1
3RB — 3-lead CONTACT
C
B
f 0.10 C
A
Pin 1
Pin 1
0.30 REF
b
E
0.30 REF
e (3x)
L (3x)
f
A
A1
D
g
d 0.08 C
COMMON DIMENSIONS
(Unit of Measure = mm)
SYMBO L
MIN
NOM
MAX
D
2.40
2.50
2.60
E
6.40
6.50
6.60
A
0.45
0.50
0.55
A1
0.0
-
0.05
e
1.60
1.70
1.80
b
NOTE
2.00 BSC
L
2.10
2.20
2.30
f
0.30
0.40
0.50
g
0.05
0.15
0.25
12/16/11
TITLE
Package Drawing Contact:
[email protected]
4
3RB, 3-lead 2.5x6.5mm Body, 2.0 mm pitch,
CONTACT PACKAGE. (Sawn)
3-lead
CONTACT Package Usage [APPLICATION NOTE]
4
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
GPC
RHB
DRAWING NO.
3RB
REV.
A
Appendix B
The following are drawings for connectors listed in Section 3.
B.1
Molex 47615-020
3-lead CONTACT Package Usage [APPLICATION NOTE]
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
5 5
B.2
Molex 105040-001
6
3-lead
CONTACT Package Usage [APPLICATION NOTE]
6
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
B.3
Molex 47275-001
3-lead CONTACT Package Usage [APPLICATION NOTE]
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014
7 7
Appendix C Revision History
Doc Rev.
Date
8977A
08/2015
Atmel Corporation
Comments
Initial document release.
1600 Technology Drive, San Jose, CA 95110 USA
T: (+1)(408) 441.0311
F: (+1)(408) 436.4200
│
www.atmel.com
© 2015 Atmel Corporation. / Rev.:Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014.
Atmel®, Atmel logo and combinations thereof, Enabling Unlimited Possibilities®, and others are registered trademarks or trademarks of Atmel Corporation in U.S. and
other countries. Other terms and product names may be trademarks of others.
DISCLAIMER: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intell ectual property right
is granted by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN THE ATME L TERMS AND CONDITIONS OF SALES LOCATED ON THE ATMEL
WEBSITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODU CTS INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL ATMEL BE
LIABLE FOR ANY DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE, SPECIAL OR INCIDENTAL DAMAGES (INCLUDING, WITHOUT LIMITATION, DAMAG ES FOR LOSS AND
PROFITS, BUSINESS INTERRUPTION, OR LOSS OF INFORMATION) ARISING OUT OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED
OF THE POSSIBILITY OF SUCH DAMAGES. Atmel makes no representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves
the right to make changes to specifications and products descriptions at any time without notice. Atmel does not make any com mitment to update the information contained herein. Unless
specifically provided otherwise, Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel products are not intended, authorized, or wa rranted for use
as components in applications intended to support or sustain life.
SAFETY-CRITICAL, MILITARY, AND AUTOMOTIVE APPLICATIONS DISCLAIMER: Atmel products are not designed for and will not be used in connection with any applications where
the failure of such products would reasonably be expected to result in significant personal injury or death (“Safety -Critical Applications”) without an Atmel officer's specific written consent.
Safety-Critical Applications include, without limitation, life support devices and systems, equipment or systems for the operation o f nuclear facilities and weapons systems. Atmel products
are not designed nor intended for use in military or aerospace applications or environments unless specifically designated by Atmel as military-grade. Atmel products are not designed nor
intended for use in automotive applications unless specifically designated by Atmel as automotive-grade.
8
3-lead
CONTACT Package Usage [APPLICATION NOTE]
8
Atmel-8977A-CryptoAuth-3-lead-CONTACT-Usage-ApplicationNote_082014