INA181A3

Part: INA181, INA2181, INA4181 — Texas Instruments

Type: Bidirectional Current-Sense Amplifier

Description: Cost-optimized, bidirectional current-sense amplifier with -0.2 V to +26 V common-mode input range and four fixed-gain options operating from a single 2.7 V to 5.5 V supply.

Operating Conditions:

• Supply voltage: 2.7–5.5 V
• Operating temperature: -40 to +125 °C
• Common-mode input voltage: -0.2 to 26 V

Absolute Maximum Ratings:

• Max supply voltage: 6 V
• Max continuous current: 8 mA (Maximum output current, IOUT)
• Max junction/storage temperature: 150 °C

Key Specs:

• Gain options: 20 V/V (A1), 50 V/V (A2), 100 V/V (A3), 200 V/V (A4)
• Gain error: ±1% max (VOUT = 0.5 V to VS - 0.5 V, TA = -40°C to +125°C)
• Offset voltage, RTI: ±150 μV max (at VIN+ = 0 V), ±500 μV max (at VIN+ = 12 V)
• Offset drift, RTI: 1 μV/°C max (TA = -40°C to +125°C)
• Bandwidth: 350 kHz (A1), 210 kHz (A2), 150 kHz (A3), 105 kHz (A4) at CLOAD = 10 pF
• Common-mode rejection ratio (CMRR): 84 dB min, 100 dB typ (VIN+ = 0 V to 26 V, TA = -40°C to +125°C)
• Slew rate: 2 V/μs typ
• Quiescent current (INA181): 260 μA max (TA = 25°C), 300 μA max (TA = -40°C to +125°C)

Features:

• Common-mode range (VCM): -0.2 V to +26 V independent of supply voltage
• Bidirectional current-sensing capability
• Matched resistor gain network in four fixed-gain options
• Single-channel (INA181), dual-channel (INA2181), and quad-channel (INA4181) configurations

Applications:

• Motor control
• Battery monitors and balancers
• Power management
• Lighting control
• Solar inverters

Package:

• DBV (SOT-23, 6-pin, 2.90 mm × 2.80 mm)
• DCK (SC70, 6-pin, 2.00 mm × 2.10 mm)
• DGS (VSSOP, 10-pin, 3.00 mm × 4.90 mm)
• DSQ (WSON, 10-pin, 2.00 mm × 2.00 mm)
• PW (TSSOP, 20-pin, 6.50 mm × 6.40 mm)

• Common-mode range (VCM): -0.2 V to +26 V
• High bandwidth: 350 kHz (A1 devices)
• Offset voltage:
• -±150 μV (maximum) at VCM = 0 V
• -±500 μV (maximum) at VCM = 12 V
• Output slew rate: 2 V/μs
• Bidirectional current-sensing capability
• Accuracy:
• -±1% gain error (maximum)
• -1-μV/°C offset drift (maximum)
• Gain options:
• -20 V/V (A1 devices)
• -50 V/V (A2 devices)
• -100 V/V (A3 devices)
• -200 V/V (A4 devices)
• Quiescent current: 260 μA maximum (INA181)

• Motor control
• Battery monitors and balancers
• Power management
• Lighting control
• Solar inverters

Typical Application Circuit

INA181, INA2181, INA4181

SBOS793H - APRIL 2017 - REVISED NOVEMBER 2023

Figure 5-1. INA181: DBV Package 6-Pin SOT-23 Top View

Table 4-1. Device Comparison

Figure 5-2. INA181: DCK Package 6-Pin SC70 Top View

Table 5-1. Pin Functions: INA181 (Single Channel)

Table 5-1. Pin Functions: INA181 (Single Channel)

Figure 5-3. INA2181: DGS Package 10-Pin VSSOP Top View

Figure 5-4. INA2181: DSQ Package 10-Pin WSON Top View

Figure 5-5. INA4181: PW Package 20-Pin TSSOP Top View

Table 5-2. Pin Functions: INA2181 (Dual Channel) and INA4181 (Quad Channel)

Table 5-2. Pin Functions: INA2181 (Dual Channel) and INA4181 (Quad Channel)

at T A = 25°C, VS = 5 V, V REF = V S / 2, V IN+ = 12 V, and VSENSE = VIN+ - VIN- (unless otherwise noted)

over operating free-air temperature range (unless otherwise noted) (1)

• (1) Operation outside the Absolute Maximum Ratings may cause permanent device damage. Absolute Maximum Ratings do not imply functional operation of the device at these or any other conditions beyond those listed under Recommended Operating Conditions. If used outside the Recommended Operating Conditions but within the Absolute Maximum Ratings, the device may not be fully functional, and this may affect device reliability, functionality, performance, and shorten the device lifetime.
• (2) VIN+ and VIN- are the voltages at the IN+ and IN- pins, respectively.
• (3) Input voltage at any pin can exceed the voltage shown if the current at that pin is limited to 5 mA.

over operating free-air temperature range (unless otherwise noted)

The INAx181 amplify the voltage developed across a current-sensing resistor as current flows through the resistor to the load or ground. The ability to drive the reference pin to adjust the functionality of the output signal offers multiple configurations, as discussed in previous sections.

• (1) For all available packages, see Section 11.
• (2) The package size (length × width) is a nominal value and includes pins, where applicable.