Hello everyone. I'm planning a project which involves using a force sensing resistor (FSR) to convert force to voltage, but I'm confused as to some details (I'm a total newb, so bear with me). I'm considering using the Interlink FSR 408, and I found a useful integration guide for it. On pages 18 and 19 of the guide, there are schematics for a voltage divider and two types of adjustable buffer. I have some questions about these:
1) Based off of the schematics, these circuits require: FSR, opamp(s), resistor(s), potentiometer(s), and... what else? A 9V battery? Anything else?
2) According to the guide, one difference between the voltage divider and the adjustable buffers is that the adjustable buffers allow adjustment of the gain. In this case, what is 'gain'? Is it simply referring to a further increase of the output voltage, perhaps a multiplier of the applied force?
3) The adjustable buffers also allow adjustment of 'output offset.' What is this? The guide states that "offsets resulting from the non-infinite FSR resistance at zero force (or bias currents) can be trimmed out with a potentiometer." Is this a long-winded version of saying that I can use a pot to eliminate extreme voltage outputs that happen when I'm not applying any force to the sensor? Or perhaps it has to do with a attaining a better force-to-voltage curve by eliminating the response of the sensor when no force is applied?
Any help would be greatly appreciated!
1) Based off of the schematics, these circuits require: FSR, opamp(s), resistor(s), potentiometer(s), and... what else? A 9V battery? Anything else?
2) According to the guide, one difference between the voltage divider and the adjustable buffers is that the adjustable buffers allow adjustment of the gain. In this case, what is 'gain'? Is it simply referring to a further increase of the output voltage, perhaps a multiplier of the applied force?
3) The adjustable buffers also allow adjustment of 'output offset.' What is this? The guide states that "offsets resulting from the non-infinite FSR resistance at zero force (or bias currents) can be trimmed out with a potentiometer." Is this a long-winded version of saying that I can use a pot to eliminate extreme voltage outputs that happen when I'm not applying any force to the sensor? Or perhaps it has to do with a attaining a better force-to-voltage curve by eliminating the response of the sensor when no force is applied?
Any help would be greatly appreciated!