ACS714 current sensor -5A to + 5A - Pololu 1185

• Supply voltages of the logic part: 4.5 V to 5.5 V
• Current consumption of the logical part: 13 mA
• Sensitivity for power supply of 5V: 0,185 V/A
• Weight of the module of 1.3 g
• Dimensions: 18 x 20.5 mm

The module consists of a printed circuit board made for the system Allegro ACS714LLCTR-05B-T. The sensor operates based on the Hall effect. The chip can be powered from a voltage in the range: 4.5 V to 5.5 V.

Basic module features:

• The system is designed for current flowing in both directions (from -5A to 5A)
• Due to the low resistance of the system (1.2 mΩ) and channeling, the power losses are very small.
• Through the use of Hall effect, the current paths are isolated from the logic part.
• The bandwidth is up to 80 kHz with the possibility of reduction by adding an additional condenser
• Precision of 1.5% at room temperature.

The sensor requires a supply voltage in the range from 4.5 V to 5 V, connected to the pins designated as VCC (+) and GND (ground). The output is a voltage signal proportional to the intensity of the measured current. When the voltage VCC is equal to 5 V, the output is centered on the half, that is 2.5 V. The output value increases by 185 mV at 1 A when the strength of the measured current is positive, otherwise, it decreases.

Additional filtering

The chip has an internal resistance filter of 1.7kΩ, the board has the condenser with the value of 1nF, which together form a low pass filter with cut-off frequency of 90 kHz. The user can change the filter when the capacitor is output onis called "filter". The limit frequency can be calculated by the formula:

F = 1 / (2πRC) = 1 / (11kΩ * (1 nF + Cf))

whereCfis the capacitance of the capacitor soldered into the "filter" pins.

• Website of the manufacturer: Pololu #1185
• Documentation of the sensor