Datasheet FS (Spectra Symbol) - 2

Schematics
V V IN R1 R V V OU O T U R2 R VO V L O T L A T G A E G DI D VI V D I E D R E R2 R IMP M ED E A D N A C N E C ( ( ) V V OU O T U T =V = V INI BU B F U F F E F R E R1 R 1 + + R 2
Fol owing are notes from the ITP Flex Sensor Workshop "The impedance buf er in the [Basic Flex Sensor Circuit] (above) is a single sided operational amplifier, used with these sensors because the low bias current of the op amp reduces errer due to source impedance of the flex sensor as voltage divider. Suggested op amps are the LM358 or LM324." "You can also test your flex sensor using the simplest circut, and skip the op amp."
"Adjustable Buffer
- a potentiometer can be added to the circuit to adjust the sensitivity range."
"Variable Deflection Threshold Switch
- an op amp is used and outputs either high or low depending on the voltage of the inverting input. In this way you can use the flex sensor as a switch without going through a microcontrol er."
"Resistance to Voltage Converter
- use the sensor as the input of a resistance to voltage converter using a dual sided supply op-amp. A negative reference voltage wil give a positive output. Should be used in situations when you want output at a low degree of bending." spectrasymbol.com Page 2 (888) 795-2283