Texas Instruments INA169NA/3K

Overview

INA169NA/3K from Texas Instruments is a high-side, unipolar current shunt monitor IC designed for precision measurement of load current via a sense resistor in systems with up to 60 V common-mode voltage. It features 1000 µA/V transconductance, ±1 mV input offset voltage (max), 120 dB typical common-mode rejection at DC, and operates from 2.7 V to 60 V supply while consuming only 60 µA quiescent current. It is used in battery chargers and power management circuits where accurate high-side sensing avoids ground path disruption.

For engineers reviewing the INA169NA/3K datasheet, INA169NA/3K pinout, INA169NA/3K application, or INA169NA/3K equivalent, key selection considerations include its 60 V common-mode range, current-output architecture requiring external RL for gain setting, –40°C to +85°C operating temperature, SOT-23-5 package compatibility, and suitability for unipolar high-side current monitoring in automotive and industrial power supplies.

Technical Context

The INA169NA/3K integrates a high-voltage precision op amp, laser-trimmed thin-film resistors, and a low-noise output transistor to enable accurate differential voltage-to-current conversion. Its input stage accepts common-mode voltages up to 60 V independent of the 2.7–60 V supply rail, supporting true high-side placement between source and load.

It delivers 1000 µA/V transconductance with ±0.1% nonlinearity error over 10–150 mV input range and maintains 100 dB CMRR up to 10 kHz. Output current drives an external load resistor (RL) to generate a voltage; bandwidth scales inversely with RL - 440 kHz at 10 kΩ, 220 kHz at 20 kΩ - enabling trade-offs between speed and gain.

Key Specifications

Pinout & Package

INA169NA/3K is housed in a 5-pin SOT-23 package (2.90 mm × 1.60 mm body size) with gull-wing leads, optimized for space-constrained PCB layouts and reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side current monitoring applications.

Compared with INA169NA/3K, INA240A1IDR offers superior DC accuracy and extended voltage range at the cost of 35× higher quiescent current, while MAX4080TASA+ provides higher common-mode headroom in a larger package with modestly reduced AC performance and CMRR - making INA169NA/3K optimal for compact, low-power 60 V high-side monitoring.

Availability

INA169NA/3K is available at Aetrix Electronics and suitable for battery chargers, industrial power supplies, automotive body control modules, and portable medical devices requiring stable component supply and long-term manufacturability.

Supply support for INA169NA/3K includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company specializing in analog and embedded processing technologies, with leadership in precision signal chain and power management solutions.

INA169NA/3K belongs to TI's high-side current sense amplifier product line, engineered for unipolar current measurement in high-common-mode-voltage applications such as power supplies, battery systems, and motor controls.

FAQ

What is the maximum common-mode voltage supported by the INA169NA/3K?

The INA169NA/3K supports a maximum common-mode input voltage of 60 V, as specified in the Recommended Operating Conditions table. This allows direct connection to high-side shunts in 48 V industrial or automotive systems without attenuation or isolation. Exceeding 60 V risks violating absolute maximum ratings and may cause permanent damage. The INA169NA/3K datasheet confirms this limit applies across its full –40°C to +85°C operating temperature range.

How does the INA169NA/3K generate its output voltage?

The INA169NA/3K outputs a current proportional to the sensed differential voltage (VSENSE = VIN+ − VIN–), with transconductance gm = 1000 µA/V. An external load resistor (RL) connected between the OUT pin and ground converts this current to a voltage (VOUT = gm × VSENSE × RL). Gain is fully determined by RL - e.g., 10 kΩ yields 10 V/V - and the device itself has no internal voltage amplifier. This architecture preserves high output impedance and simplifies gain scaling.

Can the INA169NA/3K measure bidirectional current?

No, the INA169NA/3K is a unipolar current shunt monitor designed only for positive differential inputs (VIN+ > VIN–). Applying reverse polarity causes output current to drop to zero without damage, but no negative current information is conveyed. For bidirectional measurement, two INA169NA/3K devices must be used in opposing configurations with external logic (e.g., comparator) to determine direction - as detailed in Figure 15 of the INA169NA/3K datasheet.

What is the operating temperature range of the INA169NA/3K?

The INA169NA/3K is specified for operation from –40°C to +85°C ambient temperature. This range is explicitly stated in the Electrical Characteristics table and distinguishes it from the INA139 variant, which operates up to +125°C. Performance parameters including offset voltage, CMRR, and transconductance are guaranteed only within this –40°C to +85°C window, and thermal derating is not defined beyond these limits.

Is the INA169NA/3K pin-compatible with the INA139 series?

Yes, the INA169NA/3K shares identical pinout, package (SOT-23-5), and terminal functions with the INA139 family. Both use pins 1–5 for OUT, GND, VIN+, VIN–, and V+, respectively. However, they differ in maximum common-mode voltage (60 V vs. 40 V), temperature range (–40°C to +85°C vs. –40°C to +125°C), and some AC specifications - so substitution requires verification of voltage and thermal margins in the target application.