Description: The Sensor Helper is a small, easy to use, comparator break-out board. A comparator is a device that compares two inputs. One of the inputs is supplied on board and is called a reference, basically a setting. The other input is what you are measuring (or comparing) the reference to. When the input you are measuring goes above or below the reference voltage the output pin (labeled "OUT") is triggered.
On the Sensor Helper board there is a small trimpot with which you can set the reference voltage. The input voltage you are checking is brought in through one of the breakout pins (labeled "IN").
The Sensor Helper was made for situations where you need to read an analog voltage and only have an output activated when the input reaches a certain level. The output voltage is at the full VCC (supply voltage), if your supply is 5 volt, the output will be 0 when input is below reference voltage or 5 volts when at or above.
There are two main benefits of the Sensor Helper:
- No programming required - Make many projects without a micro controller. Connect an analog sensor to the Sensor Helper, connect the output to a device you want to control, set the reference voltage trim pot to trigger at the desired setting = done!
- Simplify your micro controller project / read and react to an analog voltage when you do not have enough (or any) analog pins. Connect the Sensor Helper's output to a digital pin and know at what reference voltage the digital pin will change. This is better than connecting an analog voltage to your digital pin and possibly damaging your device and / or having strange and unpredictable results.
Example projects: With no programming required:
- Connecting a temperature sensor to the input pin, set the trim pot's reference voltage to activate when a certain temperature is reached, then have the output activate a cooling fan.
- Connect a pressure sensor to the input, and the output to open a door when the correct weight is sensed.
- Light-dark sensor to control lights.
- Humidity sensor to watering pump for your plants.
- etc ....
Technical Specs:
- Input voltage: 1.6 to 5.5 volts
- Output: Push-Pull, Compatible CMOS and TTL, Non-inverting
- Hysteresis: Approximately [0.12volts @ 5 volts][0.07v @ 3v] (R1 4.7k and RF 200k ohms)
- Temperature range: -40°c to +85°c
- Size: 0.75x0.5" (12.7x19.05mm)
- Weight: 1.2 grams (with 4 pin male header solder in place)
Includes:
- 1x SpikenzieLabs MCP6541 Comparator Breakout (AKA The Sensor Helper)
- 1x Set of male pin headers (not soldered in place)
Also required:
- Trimpot adjustment tool (We use a thin small flat screwdriver 1.5 - 1.7mm)
- Soldering supplies (To attach pin headers or wires)
Usage note: The pad with hole marked "TP", is a test point. Useful incase you want to check your reference voltage's approximate value. Want to know even more? The actual reference trigger point may differ slightly due to hysteresis, see the formula in the MCP6541 Spec sheet (Page 18 EQUATION 4-1).
Documentation:
U.S. - English + Int.
