The INA138 and INA168 are high-side, unipolar, current shunt monitors. Wide input common-mode voltage range, low quiescent current, and tiny SOT-23 packaging enable use in a variety of applications.

Input common-mode and power-supply voltages are independent and can range from 2.7 V to 36 V for the INA138 and 2.7 V to 60 V for the INA168. Quiescent current is only 25 µA, which permits connecting the power supply to either side of the current measurement shunt with minimal error.

The device converts a differential input voltage to a current output. This current is converted back to a voltage with an external load resistor that sets any gain from 1 to over 100. Although designed for current shunt measurement, the circuit invites creative applications in measurement and level shifting.

Both the INA138 and INA168 are available in SOT23-5 and are specified for the -40°C to 125°C temperature range.

Key Features

• Complete Unipolar High-Side Current Measurement Circuit
• Wide Supply and Common-Mode Range
• INA138: 2.7 V to 36 V
• INA168: 2.7 V to 60 V
• Independent Supply and Input Common-Mode Voltages
• Single Resistor Gain Set
• Low Quiescent Current (25 µA Typical)
• Wide Temperature Range: -40°C to +125°C
• 5-Pin SOT-23 Package