12.1 Layout Guidelines

• Connect the input pins to the sensing resistor using a Kelvin or four-wire connection. This connection technique makes sure that only the current-sensing resistor impedance is detected between the input pins. Poor routing of the current-sensing resistor commonly results in additional resistance present between the input pins. Given the very low ohmic value of the current resistor, any additional high-current carrying impedance can cause significant measurement errors.
• Place the power-supply bypass capacitor as close as possible to the supply and ground pins. The recommended value of this bypass capacitor is 0.1 μF. Add additional decoupling capacitance to compensate for noisy or high-impedance power supplies.

12.2 Layout Example

Figure 35. INA20x-Q1 Layout Example