ASTM F1661-09

Standard Test Method for Determining the Contact Bounce Time of a Membrane Switch

SIGNIFICANCE AND USE
Contact bounce time is essential to manufacturers and users when designing interface circuitry because it specifies the time delay necessary in the decoder circuitry to avoid any false signals caused by contact bounce. Allowing for time delay makes the switch operation considerably more reliable.
SCOPE
1.1 This test method covers the determination of the contact bounce time of a membrane switch.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 14-Jun-2009
• ICS: 29.120.40 - Switches
• Technical Committee: F01 - Electronics
• Drafting Committee: F01.18 - Printed Electronics

Relations

• Replaces: ASTM F1661-08 - Standard Test Method for Determining the Contact Bounce Time of a Membrane Switch
• Effective Date: 15-Jun-2009
• Replaced By: ASTM F1661-09(2015) - Standard Test Method for Determining the Contact Bounce Time of a Membrane Switch
• Effective Date: 01-Jun-2015
• Referred By: ASTM F1596-15 - Standard Test Method for Exposure of a Membrane Switch or Printed Electronic Device to Temperature and Relative Humidity
• Effective Date: 15-Jun-2009

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F1661 − 09
StandardTest Method for
Determining the Contact Bounce Time of a Membrane
1
Switch
This standard is issued under the fixed designation F1661; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope it constantly remains above the SUTV after the last instant it
falls below the SLTV. If V does not fall below SLTV during
M
1.1 This test method covers the determination of the contact
the time interval, T = 0, (see Fig. 2).
CBM
bounce time of a membrane switch.
3.1.4 lower transition voltage, LTV—the voltage at which
1.2 The values stated in SI units are to be regarded as
the switched logic device transitions to an “off” state.
standard. No other units of measurement are included in this
3.1.5 membrane switch—a momentary switching device in
standard.
which at least one contact is on, or made of, a flexible
1.3 This standard does not purport to address all of the
substrate.
safety concerns, if any, associated with its use. It is the
3.1.6 resistor, load, R —loadresistanceinserieswithswitch
responsibility of the user of this standard to establish appro- L
under test.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
3.1.7 specified lower transition voltage, SLTV— minimum
allowable LTV.
2. Referenced Documents
3.1.8 specified upper transition voltage, SUTV— minimum
2
2.1 ASTM Standards:
allowable UTV.
D2240 Test Method for Rubber Property—Durometer Hard-
3.1.9 upper transition voltage, UTV—the voltage at which
ness
the switched logic device transitions to an ''on” state.
F2592 Test Method for Measuring the Force-Displacement
3.1.10 voltage, measured, V —voltage measured across
of a Membrane Switch M
load Resistor (R ) by the oscilloscope and measured on it’s
F1680 Test Method for Determining Circuit Resistance of a L
screen or voltage measured across the switch under test when
Membrane Switch
a contact bounce measuring device is used.
3. Terminology
4. Significance and Use
3.1 Definitions:
4.1 Contact bounce time is essential to manufacturers and
3.1.1 contact bounce—intermittent contact opening and
userswhendesigninginterfacecircuitrybecauseitspecifiesthe
contact closure that may occur after switch operation.
time delay necessary in the decoder circuitry to avoid any false
3.1.2 contact bounce time (break), T —the time period
CBB
signals caused by contact bounce. Allowing for time delay
measured from the first instant V is equal to the SUTV until
M
makes the switch operation considerably more reliable.
it constantly remains below the SLTV after the last instant it
rises above the SUTV. If V does not rise above SUTV during
M 5. Interference
the time interval, T = 0, (see Fig. 1).
CBB
5.1 The following parameters may affect the results of this
3.1.3 contact bounce time (make), T —the time period
CBM
test:
measured from the first instant V is equal to the SLTV until
M
5.1.1 Mechanical probe materials (hardness) and speed will
affect results.
1
This test method is under the jurisdiction of ASTM Committee F01 on
6. Apparatus
Electronics and is the direct responsibility of Subcommittee F01.18 on Membrane
Switches.
6.1 Test Probe, built to either of the configuration shown in
Current edition approved June 15, 2009. Published July 2009. Originally
Fig. 3 and Fig. 4 are acceptable but must be made of an inert
approved in 1995. Last previous edition approved in 2008 as F1661 – 08. DOI:
10.1520/F1661-09.
elastomeric material with a hardness number equivalent to
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
A/45 6 5 as measured in accordance withTest Method D2240.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Test probes that do not meet the above criteria must be fully
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. specified and recorded.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
F1661 − 09
FIG. 4 Test Probe Option
FIG. 1 Contact Bounce on Switch Break
7.1.1 Determine Fmax or Fc (whichever is greater) per Test
Method F2592.
7.1.2 Determine switch resistance (R ) per Test Method
S
F1680.
7.1.3 Secure switch on test surface.
7.1.4 Connect switch terminals as shown in Fig. 5 so that:
R 5 10 to 100 times R
L S
7.1.5 Adjust oscilloscope to initial settings as follows:
7.1.5.1 One half to 1.0 V/cm vertical, and
7.1.5.2 Two to 3 ms/cm horizontal.
7.1.5.3 Set SUTV per Fig. 6 if known. If not known, default
SUTV wil
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:F 1661–08 Designation:F 1661–09
Standard Test Method for
Determining the Contact Bounce Time of a Membrane
1
Switch
This standard is issued under the fixed designation F 1661; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the determination of the contact bounce time of a membrane switch.
1.2
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D 2240 Test Method for Rubber PropertyDurometer Hardness
F 2592 Test Method for Measuring the Force-Displacement of a Membrane Switch
F 1680 Test Method for Determining Circuit Resistance of a Membrane Switch
3. Terminology
3.1 Definitions:
3.1.1 contact bounce—intermittent contact opening and contact closure that may occur after switch operation.
3.1.2 contact bounce time (break), T —the time period measured from the first instant V is equal to the SUTV until it
CBB M
constantly remains below the SLTV after the last instant it rises above the SUTV. If V does not rise above SUTV during the time
M
interval, T = 0, (see Fig. 1).
CBB
3.1.3 contact bounce time (make), T —the time period measured from the first instant V is equal to the SLTV until it
CBM M
constantly remains above the SUTV after the last instant it falls below the SLTV. If V does not fall below SLTV during the time
M
interval, T = 0, (see Fig. 2).
CBM
3.1.4 lower transition voltage, LTV—the voltage at which the switched logic device transitions to an “off” state.
3.1.5 membrane switch—a momentary switching device in which at least one contact is on, or made of, a flexible substrate.
3.1.6 resistor, load, R —load resistance in series with switch under test.
L
3.1.7 specified lower transition voltage, SLTV— minimum allowable LTV.
3.1.8 specified upper transition voltage, SUTV— minimum allowable UTV.
3.1.9 upper transition voltage, UTV—the voltage at which the switched logic device transitions to an 88on” state.
3.1.10 voltage, measured, V —voltage measured across load Resistor (R ) by the oscilloscope and measured on it’s screen or
M L
voltage measured across the switch under test when a contact bounce measuring device is used.
4. Significance and Use
4.1 Contact bounce time is essential to manufacturers and users when designing interface circuitry because it specifies the time
delay necessary in the decoder circuitry to avoid any false signals caused by contact bounce. Allowing for time delay makes the
switch operation considerably more reliable.
5. Interference
5.1 The following parameters may affect the results of this test:
1
This test method is under the jurisdiction of ASTM Committee F01 on Electronics and is the direct responsibility of Subcommittee F01.18 on Membrane Switches .
Current edition approved Nov. 1, 2008. Published December 2008. Originally approved in 1995. Last previous edition approved in 2002 as F1661–96(2002).
Current edition approved June 15, 2009. Published July 2009. Originally approved in 1995. Last previous edition approved in 2008 as F 1661 – 08.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
F 1661–09
FIG. 1 Contact Bounce on Switch Break
FIG. 2 Contact Bounce on Switch Make
5.1.1 Mechanical probe materials (hardness) and speed will affect results.
6. Apparatus
6.1 Test Probe, built to either of the configuration shown in Fig. 3 and Fig. 4 are acceptable but must be made of an inert
elastomeric material with a hardness number equivalent to A/45 6 5 as measured in accordance with Test Method D 2240. Test
probes that do not meet the above criteria must be fully specified and recorded.
6.2 Test
...