1 Features
• Low power:
– Supply voltage, VS: 1.7 V to 5.5 V
– Shutdown current: 100 nA (max INA191)
– Quiescent current: 43 μA at 25 °C (INA191)
• Low input bias currents: 100 pA (typical)
(enables microamp current measurement)
• Bidirectional current measurement (INA2191)
• Accuracy:
– ±0.25% max gain error (A2 to A5 devices)
– 7-ppm/°C gain drift (maximum)
– ±12 μV (maximum) offset voltage
– 0.13-μV/°C offset drift (maximum)
• Wide common-mode voltage: –0.2 V to +40 V
• Gain options:
– INAx191A1: 25 V/V
– INAx191A2: 50 V/V
– INAx191A3: 100 V/V
– INAx191A4: 200 V/V
– INAx191A5: 500 V/V
• Packages:
– INA191: 0.895-mm2 DSBGA
– INA2191: 1.79-mm2 DSBGA

2 Applications
• Notebook computers
• Cell phones
• Battery-powered devices
• Telecom equipment
• Power management
• Battery chargers

3 Description
The INAx191 is a low-power, voltage-output,
current-shunt monitor (also called a current-sense
amplifier) that is commonly used for overcurrent
protection, precision-current measurement for system
optimization, or in closed-loop feedback circuits. This
device can sense drops across shunts at commonmode
voltages from –0.2 V to +40 V, independent
of the supply voltage. The low input bias current
of the INAx191 permits the use of larger currentsense
resistors, and thus provides accurate current
measurements in the μA range. Five fixed gains
are available: 25 V/V, 50 V/V, 100 V/V, 200 V/V,
or 500 V/V. The low offset voltage of the zero-drift
architecture extends the dynamic range of the current
measurement, and allows for smaller sense resistors
with lower power loss while still providing accurate
current measurements.
The INA191 operates from a single 1.7-V to 5.5-
V power supply, drawing a maximum of 65 μA of
supply current when enabled and only 100 nA when
disabled. The device is specified over the operating
temperature range of –40 °C to +125 °C, and offered
in a DSBGA-6 (INA191) and DSBGA-12 (INA2191)
packages.