Texas Instruments INA296B4IDDFR

Overview

INA296B4IDDFR from Texas Instruments is a bidirectional, ultra-precise current sense amplifier with 100V/V fixed gain, −5V to 110V common-mode input range, 1.1MHz bandwidth, and ±150µV max input offset voltage. It operates from 2.7V–20V supply and delivers fast 1µs settling to 1% for high-speed overcurrent detection in 48V DC/DC converters and battery management systems.

For engineers reviewing the INA296B4IDDFR datasheet, INA296B4IDDFR pinout, INA296B4IDDFR application, or INA296B4IDDFR equivalent, this page provides verified technical context, package-specific pin functions, real-world application mappings, and validated alternative options for precision high-voltage current sensing designs.

Technical Context

The INA296B4IDDFR uses a zero-drift topology enabling ±150µV max input offset and ±0.1% max gain error across −40°C to +125°C. Its input bias current remains constant at 35µA (typ) up to 110V common-mode voltage - independent of V_CM - unlike conventional high-voltage amplifiers.

It supports configurable unidirectional or bidirectional operation via REF1/REF2 pins, with output centered at (V_REF1 + V_REF2)/2. The 100V/V gain version achieves 36nV/√Hz input-referred noise and 8V/µs slew rate, optimized for low-shunt-resistor, high-dynamic-range applications.

Key Specifications

Pinout & Package

INA296B4IDDFR is packaged in an 8-pin SOT-23 (DDF) measuring 2.9mm × 2.8mm, optimized for space-constrained 48V power modules and compact DC/DC converters.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current sense amplifier applications.

Compared with INA296B4IDDFR, INA240A4IDR trades bandwidth and common-mode range for lower cost and wider temp spec (−40°C to +150°C), while MAX40056ASA+T offers superior speed but sacrifices high-voltage robustness - making INA296B4IDDFR optimal for 48V–60V infrastructure demanding both precision and ruggedness.

Availability

INA296B4IDDFR is available at Aetrix Electronics and suitable for 48V DC/DC converters, 48V battery management systems, and macro remote radio unit (RRU) power monitoring requiring stable component supply and long-term production continuity.

Supply support for INA296B4IDDFR 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 leader specializing in analog and embedded processing technologies, with decades of expertise in precision signal conditioning and high-voltage interface ICs.

The INA296x product line was designed specifically for ultra-precise, high-bandwidth current sensing in next-generation 48V power architectures - including server PSUs, EV auxiliary systems, and 5G infrastructure - where accuracy, speed, and common-mode resilience are non-negotiable.

FAQ

What is the maximum common-mode voltage the INA296B4IDDFR can withstand without damage?

The INA296B4IDDFR has a survival rating of −20V to 120V, meaning it can endure transient overvoltage events such as load dump or reverse battery connection up to 120V without permanent damage. Its operational common-mode range is −5V to 110V, which defines the valid input voltage window for accurate current measurement. This dual-rating structure ensures robustness in harsh 48V automotive and telecom environments where voltage spikes are common. The INA296B4IDDFR maintains functionality throughout its operational range without requiring external clamping or attenuation circuits.

How does the REF1 and REF2 pin configuration affect bidirectional current measurement in the INA296B4IDDFR?

In the INA296B4IDDFR, connecting REF1 to V_S and REF2 to GND centers the output at V_S/2, enabling true bidirectional sensing: positive V_SENSE drives output above mid-supply, negative V_SENSE drives it below. This configuration allows a single-ended ADC to resolve both charge and discharge currents in 48V BMS applications. The internal reference divider achieves ±0.02% accuracy, ensuring minimal zero-point error. The INA296B4IDDFR's matched resistor network guarantees stable centering across temperature, eliminating software-based offset compensation in production firmware.

Can the INA296B4IDDFR operate with a 3.3V supply while sensing on a 48V bus?

Yes, the INA296B4IDDFR operates from 2.7V to 20V supply and supports common-mode inputs up to 110V - completely independent of V_S. With a 3.3V supply, it accurately measures differential voltage across a shunt on a 48V bus, delivering a 100× amplified output referenced to (REF1 + REF2)/2. Output swing is limited to 20mV above GND and ~350mV below 3.3V, so REF pins must be set accordingly (e.g., REF1 = 3.3V, REF2 = 0V → V_OUT centered at 1.65V). This capability eliminates level-shifters in mixed-voltage systems and reduces system power overhead. The INA296B4IDDFR maintains full 1.1MHz bandwidth and ±150µV offset even at 3.3V V_S.

What is the input bias current behavior of the INA296B4IDDFR across its common-mode range?

The INA296B4IDDFR exhibits a constant typical input bias current of 35µA per input pin - independent of common-mode voltage from −5V to 110V. Unlike many high-voltage current sense amplifiers whose bias current scales with V_CM, this design prevents gain error drift caused by shunt resistor self-heating or bus voltage variation. At 110V V_CM, the 35µA bias introduces only 3.5µV error across a 100mΩ shunt, preserving measurement integrity in precision applications like cell-level BMS monitoring. This stable bias enables accurate low-current sensing (<1A) without recalibration across wide input voltage ranges. The INA296B4IDDFR's architecture ensures this performance is maintained across −40°C to +125°C.

Is the INA296B4IDDFR pin-compatible with other members of the INA296x family?

Yes, all INA296x variants - including INA296A1–A5 and INA296B1–B5 - share identical 8-pin DDF (SOT-23), DGK (VSSOP), and D (SOIC) packages and pinouts. The INA296B4IDDFR uses the same IN+, IN−, OUT, VS, REF1, REF2, GND, and NC connections as INA296A4IDDFR or INA296B2IDDFR. This allows direct substitution within the same package footprint when changing gain or precision grade, provided the system accommodates the corresponding offset and gain error specifications. No PCB redesign is needed for gain upgrades or accuracy tier changes - only firmware or reference voltage adjustments may be required to maintain output scaling. The INA296B4IDDFR's mechanical and electrical compatibility simplifies design reuse across product families.