Sensor Electrical Characteristic(Analog Output)

Using Arduino Sensors
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Hi,
I am thinking of using a Panasonic Analog PIR Sensor (EKMC2605113K) (EKM - Horizontally Wide Detection) for Motion detection. I will be using Arduino 33 BLE Sense for this project.
It will be really helpful if someone can clarify/correct upon the queries/assumptions I have about the Electrical Characteristic Specification of the Sensor :
These are from the Panasonic Website for reference.

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  1. The Operating Voltage ,V_dd, is mentioned as Max 5.5 and Min 3.0 V and current consumption is Max 350 microAmps :
    So this means I can use it on Arduino 33 Ble which can supply 3.3V. Am I correct?

  2. Analog Output Saturated Voltage (V_H and V_L) are min 1.9V and Max 0.2V. The Output current during detection is mentioned as 200 microAmps :
    Can someone explain what this signifies?

    • Does this mean the maximum and min voltage at the sensor output will be 1.9V and 0.2V respectively during detection? Or does this just mean that the linearity range of the sensor is between 1.9V and 0.2V .
    • Does this also mean that the maximum output voltage from the sensor is 1.9V ( In general, how to get the maximum output voltage of the sensor, shall I add the output offset voltage(max) to this Saturation voltage?)

  3. Output Offset Voltage(at non-detection), V_Off, is mentioned as V_Max = 1.2 , V_Avg= 1.1V and V_Min = 1.0V :
    I understand , in case of Op-Amp this refers to voltage at the output when the inputs of the Op-Amp is shorted. What does this attribute signifies w.r.t to this sensor?

  4. It is highlighted that I need to measure the Output Offset Voltage before setting the threshold window for detection. Am I correct in my understanding that this offset voltage will be the result of environment when there is no detection and this voltage (Offset Voltage Specification of 1.2V to 1V) will always be there at the output of the sensor and when there a detection then a Voltage (in addition to the offset voltage) of 0.2V to 1.9V (from the Analog Saturated Voltage Specification).

I will be really grateful if someone can guide me or refer me to resources which can give me an understanding about these Electrical Characteristics specifications w.r.t to sensors. I am just starting in this Embedded systems domain and please forgive me if I am unable to get something trivial. I read up on Op-amps but am having a hard time relating these to a sensor specification.

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Link?

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These are the relevant link: (These is no specific model page but just a catalog for PIR sensors from Panasonic

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It looks like the output sits at around 1.1V when stationary, varying in the range 0.2V to 1.9V when a signal is detected. The output is fairly high impedance (max output current 0.2mA)

The way these sensors work is by sensing differences, not absolute values, and the actual quiescent output voltage has a significant manufacturing spread by the look of it - you'll have to calibrate for this per device (and possibly this varies with sensor temperature too).

I don't understand why you're not choosing a digital sensor which does all the thresholding for you and is simple to use. This sensor will be complicated to use, but you'll be able to program your own detection criteria.

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The temperature of the environment will vary a lot as I am planning to use it on camera traps, which will trigger a camera based on Motion detection algorithm using Arduino Nano 33 BLE. To reduce false positives, which PIR sensors are prone to , I am planning to use two or three coupled sensors with different overlapping field of view and using an intersection region( of the FOV of these sensors for final motion detection) which will be aligned with camera FOV. I thought using analog sensor will give me better motion signatures which can be fed into Arduino Nano 33, so instead of using Digital Sensors which can be really difficult to tune for sensitivity, I thought of using Machine Learning algorithm for motion detection.

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Ah, that makes sense - good luck.

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