10.1 Layout Guidelines

• Connect the input pins to the sensing resistor using a Kelvin or 4-wire connection. This connection technique ensures 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 causes significant measurement errors.
• The power-supply bypass capacitor must be placed as close as possible to the supply and ground pins. The recommended value of this bypass capacitor is 0.1 μF. Additional decoupling capacitance can be added to compensate for noisy or high-impedance power supplies.

10.2 Layout Example

Figure 39. INA20x Layout Example