DESCRIPTION
Most current-measuring devices are only good for low side measuring. That means that unless you want to get a battery involved, you have to stick the measurement resistor between the target ground and true ground. This can cause problems with circuits since electronics tend to not like it when the ground references change and move with varying current draw. This chip is much smarter - it can handle high side current measuring, up to +26VDC, even though it is powered with 3 or 5V. It will also report back that high side voltage, which is great for tracking battery life or solar panels.
A precision amplifier measures the voltage across the 0.1 ohm, 1% sense resistor. Since the amplifier maximum input difference is ±320mV this means it can measure up to ±3.2 Amps. With the internal 12 bit ADC, the resolution at ±3.2A range is 0.8mA. With the internal gain set at the minimum of div8, the max current is ±400mA and the resolution is 0.1mA. Advanced hackers can remove the 0.1 ohm current sense resistor and replace it with their own to change the range (say a 0.01 ohm to measure up 32 Amps with a resolution of 8mA)
Usage is simple. Power the sensor itself with 3 to 5VDC and connect the two I2C pins up to your microcontroller. Then connect your target power supply to VIN+ and the load to ground to VIN-.
TECHNICAL DETAILS
- Operating Voltage: 3.3V - 5V
- Measuring Range: Up to 26V DC, 3.2A
- Resolution: 0.8mA (For 0.1mA resolution, set the internal gain at the minimum of div8 - The max current is ±400mA)
SHIPPING LIST
- 1x INA219 Voltage Current Sensor
- 1x 6-pin Male Header
- 1x 3.5mm Terminal Plug