Product Description
2.7 to 36V, 800kHz Variable gain current sense amplifier
Description
The INA138 and INA168 (INA1x8) are high-side, unipolar, current shunt monitors. Wide input commonmode 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.
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
Applications
• Current Shunt Measurement: – Telephone, Computers
• Portable and Battery-Backup Systems
• Battery Chargers
• Power Management
• Cell Phones
• Precision Current Source
