> For the complete documentation index, see [llms.txt](https://learn.pakronics.com.au/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://learn.pakronics.com.au/seed-studio/grove-modules/others/grove-differential_amplifier_v1.2.md).

# Grove Differential Amplifier v1.2

![](https://raw.githubusercontent.com/SeeedDocument/Grove-Differential_Amplifier_v1.2/master/img/Grove-Differential_Amplifier_v1.2.jpg)

This Grove is designed for precise differential-input amplification. Input the differential signals of your sensor to this module through the male pins, then your Arduino will get a precisely amplified output from the Grove interface. The gain scale factor is selectable. You can get a 35 times or 1085 times amplification via a switch on the board.

[![](https://raw.githubusercontent.com/SeeedDocument/common/master/Get_One_Now_Banner.png)](http://www.seeedstudio.com/Grove-Differential-Amplifier-p-1284.html)

## Features

* High amplifying precision
* Selectable scale factor
* Can be conveniently read by Arduino

!!!Tip More details about Grove modules please refer to [Grove System](http://wiki.seeed.cc/Grove_System/)

## Applications

* Data acquisition
* Battery operated systems
* Pressure and temperature bridge amplifiers
* General purpose instrumentation

## Specifications

| Item              | Min       | Typical | Max            | Unit |   |
| ----------------- | --------- | ------- | -------------- | ---- | - |
| Operating Voltage | 2.7       | 5.0     | 5.5            | VDC  |   |
| Input Voltage     | 0.1       | \\\\    | (Vcc-0.8)/Gain | mV   |   |
| Output Voltage    | 0         | \\\\    | Vcc-0.80       | mV   |   |
| Gain              | Select 35 | /       | 35             | /    | / |
| Select 1085       | /         | 1085    | /              |      |   |

## Platforms Supported

## Usage

**1. Sensor Choosing**

The amplifier can turn signals in mA scale up to A scale. Before using it, make sure the output range of your sensor is in mA scale. For example, [Weight Sensor](https://app.gitbook.com/Weight_Sensor-Load_Cell-0-500g) is one of them.

**2. Connector Reforming**

To pair the weight sensor up with the male pins on the amplifier, female connectors need to be soldered on its wires.

![](https://raw.githubusercontent.com/SeeedDocument/Grove-Differential_Amplifier_v1.2/master/img/Solder.jpg)

**3. Hardware Hookup**

Connect the weight sensor to the amplifier as the picture depicts below.

![](https://raw.githubusercontent.com/SeeedDocument/Grove-Differential_Amplifier_v1.2/master/img/Connect5.jpg)

**4. Measurement**

Copy and paste the demo code below to Arduino IDE and upload it.

```
    void setup()
    {
      Serial.begin(9600);
      Serial.println("start");
    }

    void loop()
    {
      int i;
      int value;
      float V,Vo;
      float Sum=0;
      for(i=0;i<10;i++)
      {
        value=analogRead(4);
        V=value*5.00/1023;
        Sum+=V;
        delay(10);
      }
      Vo=Sum/10;
      Serial.print("Output score:");
      Serial.println(Vo);
      delay(1000);
    }
```

You can view the amplified signals via serial monitor. For the value of the input signal, you need to use the multimeter to measure the voltage difference between VIN+ and VIN-.

## Resources

* [v1.2 Eagle File](https://raw.githubusercontent.com/SeeedDocument/Grove-Differential_Amplifier_v1.2/master/res/Grove-Differential_Amplifier_v1.2_eagle.zip)
* [v1.2 Schematic](https://raw.githubusercontent.com/SeeedDocument/Grove-Differential_Amplifier_v1.2/master/res/Grove-Differential_Amplifier_v1.2.pdf)
* [INA132 Datasheet](https://raw.githubusercontent.com/SeeedDocument/Grove-Differential_Amplifier_v1.2/master/res/Ina132.pdf)