Interlink electronics FSR Integration Manual Download Page 2

Page: 2 / 15

www.interlinkelectronics.com

Force Sensing Linear Potentiometer (FSLP)

Integration Guide

Table of Contents

1.0

Introduction

.................................................................................................................... 1

2.0

Scope

................................................................................................................................ 1

3.0

Theory of Operation

.................................................................................................... 2

4.0

Mounting and Connection

......................................................................................... 5

4.1

Mounting............................................................................................................. 5

4.2

FSLP Types........................................................................................................ 5

4.3

Crimp Terminal Connections (10cm and derivatives only) ................................ 7

4.4

FFC Connection Method .................................................................................... 8

5.0

Measurement Techniques and Algorithms

.......................................................... 9

5.1

Measuring Position........................................................................................... 10

5.2

Measuring Pressure ......................................................................................... 10

6.0

Actuator

......................................................................................................................... 12

7.0

Orderable Part Numbers

.......................................................................................... 12

8.0

Intellectual Property & Other Legal Matters

.................................................... 12

9.0

Contact Interlink Electronics

................................................................................ 13

Summary of Contents for FSR

Page 1: ...eter FSLP Integration Guide Interlink Electronics FSR Force Sensing Resistors Force Sensing Linear Potentiometer FSLP Integration Guide Document P N 94 00022 Rev C Interlink Electronics and the six dot logo are registered trademarks of Interlink Electronics Inc ...

Page 2: ...unting and Connection 5 4 1 Mounting 5 4 2 FSLP Types 5 4 3 Crimp Terminal Connections 10cm and derivatives only 7 4 4 FFC Connection Method 8 5 0 Measurement Techniques and Algorithms 9 5 1 Measuring Position 10 5 2 Measuring Pressure 10 6 0 Actuator 12 7 0 Orderable Part Numbers 12 8 0 Intellectual Property Other Legal Matters 12 9 0 Contact Interlink Electronics 13 ...

Page 3: ...or media players mobile phones control panels medical instruments and home entertainment devices Measurement is simple enough that it can be accomplished directly with the device s host processor without the need for a dedicated microprocessor The purpose of this document is to guide users through the successful integration of the Interlink Electronics FSLP 2 0 Scope This Integration Guide provide...

Page 4: ... by a spacer around the edges and by the rigidity of the two membranes One of the membranes has two sets of fingers which are interdigitated and electrically distinct each set connects to one trace on the tail The other membrane is coated with FSR ink When the two layers are pressed together the FSR ink shorts the two traces together with a resistance that depends on applied force Figure 1 Explode...

Page 5: ... connected to either end of a printed fixed resistor and a sense line Silver fingers orthogonally protrude along the entire length of the fixed resistor These silver fingers are interdigitated with the sense line When the FSR ink and conductor membranes are pressed together the sense line is shorted to a point along the fixed resistor through the orthogonally protruding fingers The resistance from...

Page 6: ... spot R2 is the resistance from the touch spot down to sensor terminal 3 Rp is connected to the junction between R1 and R2 by the user s touch As the user varies the touch spot from the top of the sensor to the bottom of the sensor R1 becomes larger and R2 becomes smaller As the user presses harder Rp decreases Rp varies from around 300kΩ at very light touches to 2kΩ at extremely heavy touches The...

Page 7: ...proper operation If the sensor is being mounted to a PCB it should be installed after PCB assembly is complete Heat generated during the soldering of components can damage the FSR When laminating the sensor be sure to use a hard roller or other depression tool to ensure proper bonding of the sensor s pressure sensitive adhesive and the removal of any air bubbles 4 2 FSLP Types 39 3 0 10 13 5 0 10 ...

Page 8: ...P Integration Guide Figure 5 Overall dimensions of the 10 cm FSLP All dimensions are in millimeters shown without crimp terminals The 10cm FSLP can be customized to shorter pre defined lengths Refer to User s Customization Guide provided with the Hardware Development Kit ...

Page 9: ...www interlinkelectronics com 7 Force Sensing Linear Potentiometer FSLP Integration Guide 4 3 Crimp Terminal Connections 10cm and derivatives only Figure 6 Crimp Terminal Connections ...

Page 10: ...onnector JST 4 pin SMT connector JST Part Number 04FM 1 0SP 1 9 TF Interlink recommends the above connector but any compatible connector may be used Refer to Figures 7 and 8 for sensor tail dimensions Figure 7 Top view of sensor tail All dimensions are in millimeters Figure 8 Side view of sensor tail All dimensions are in millimeters ...

Page 11: ...asuring microprocessor is very simple and requires only one external component The microprocessor will need two general purpose IO GPIO pins and two GPIO analog to digital converter ADC pins The GPIOs should be able to go into high impedance mode 1MΩ and the ADCs should be able to measure from 0 to Vcc The pinout for the standard FSLP and 10cm FSLP are identical Figure 9 FSLP Sensor pin out Figure...

Page 12: ...ult from very light pressure on the sensor Depending on the input impedance of the ADC allowing five to ten microseconds before taking the measurement will help to increase the sensitivity of the sensor and detect light touches Step 4 Take the measurement Start the A D conversion and store the result An 8 bit ADC will yield a result within 0 and 255 counts This value is proportional to the physica...

Page 13: ...0 can be calculated as The current I is the same current that flows through Rp No current flows through R2 therefore the voltage drop across Rp is simply V1 V2 Rp now be calculated using Because the value of Rp decreases with force what we really want is the reciprocal of the expression above R0 is a constant therefore we can think of it as a scaling factor The scaling factor should be a convenien...

Page 14: ...00024 FSLP 10cm Sensor with Female Contacts Housing 34 00025 FSLP 10cm Sensor with FFC Tail 34 00034 8 0 Intellectual Property Other Legal Matters Interlink Electronics holds several domestic and international patents for its Force Sensing Resistor technology FSR and Force Sensing Resistor are company trademarks All other trademarks are the property of their respective owners The product informati...

Page 15: ...Electronics Inc 546 Flynn Road Camarillo CA 93012 USA Phone 1 805 484 8855 Fax 1 805 484 9457 Web www interlinkelectronics com Sales and support sales interlinkelectronics com Japan Japan Sales Office Kannai Keihin Bldg 10F 1004 2 4 2 Ougi cyo Naka ku Yokohama shi Kanagawa ken 231 0027 Japan Phone 81 45 263 6500 Fax 81 45 263 6501 Web www interlinkelec co jp 13 ...

Search results

Summary of Contents for FSR

Reviews:

Related manuals for FSR

Brands by name

Popular brands

Interlink electronics FSR, Integration Manual

Search results

Summary of Contents for FSR

Reviews:

Related manuals for FSR

Brands by name

Popular brands