Texas Instruments INA296A3IDDFR

Overview

INA296A3IDDFR from Texas Instruments is a bidirectional, ultra-precise current sense amplifier optimized for 48V systems, featuring 50V/V fixed gain, −5V to 110V common-mode input range, 1.1MHz bandwidth, and ±10µV max offset voltage. It enables high-accuracy DC and transient current monitoring in high-side, low-side, or inline shunt configurations within 48V DC/DC converters and battery management systems.

For engineers reviewing the INA296A3IDDFR datasheet, INA296A3IDDFR pinout, INA296A3IDDFR application, or INA296A3IDDFR equivalent, this page delivers verified specifications, package mapping (SOT-23-8), functional pin roles, real-world use cases in 48V infrastructure, and two validated alternative parts with documented technical and application differences.

Technical Context

The INA296A3IDDFR employs a zero-drift, precision topology that maintains ±10µV max input offset and ±0.01% max gain error across −40°C to +125°C, with ±1 ppm/°C gain drift. Its input bias current remains constant at 35µA (typ) up to 110V common-mode voltage - independent of V_CM - enabling accurate low-leakage sensing in high-voltage rails.

It supports configurable unidirectional or bidirectional operation via dual reference pins (REF1/REF2), allowing output centering at mid-supply (e.g., V_S/2) or rail-referenced operation. The 8V/µs slew rate and 1µs 1% settling time support fast overcurrent detection in 48V PSU and RRU protection circuits.

Key Specifications

Pinout & Package

INA296A3IDDFR is housed in an 8-pin SOT-23 package (DDF), measuring 2.9mm × 2.8mm, with exposed pad for thermal performance in space-constrained 48V PSU modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA296A3IDDFR, INA240A3IDR trades precision and speed for cost in non-telecom industrial use, while MAX40056ATA+T lacks the −5V to 110V common-mode range and dual-reference flexibility needed for robust 48V system monitoring.

Availability

INA296A3IDDFR 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 INA296A3IDDFR 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 delivering analog and embedded processing solutions, with deep expertise in precision signal chain and high-voltage power management ICs.

The INA296x product line was designed specifically for ultra-precise, high-bandwidth current sensing in next-generation 48V infrastructure - including datacenter PSUs, telecom RRUs, and EV-derived energy storage systems - where rail independence and sub-microsecond response are mandatory.

FAQ

What is the maximum common-mode voltage the INA296A3IDDFR can withstand during normal operation?

The INA296A3IDDFR operates continuously across a common-mode input range of −5V to 110V. This allows direct connection to 48V buses, negative auxiliary rails, and fault conditions up to 110V without damage or performance degradation. Its survival rating extends to −20V to 120V, but sustained operation above 110V is outside specified conditions. The INA296A3IDDFR maintains full precision and bandwidth throughout its operational V_CM range.

How does the INA296A3IDDFR achieve bidirectional current sensing without external components?

The INA296A3IDDFR achieves true bidirectional sensing using its dual reference inputs (REF1 and REF2). By setting these pins to different potentials - typically V_S and GND - the internal divider centers the output at V_S/2. A positive V_SENSE drives OUT above V_S/2; a negative V_SENSE drives it below. This eliminates need for external op-amps or level shifters. The INA296A3IDDFR's architecture guarantees monotonic, rail-independent behavior across the full −5V to 110V common-mode range.

Can the INA296A3IDDFR be used with a 3.3V supply while monitoring a 48V rail?

Yes. The INA296A3IDDFR's supply voltage (V_S) and common-mode input range are fully independent: it operates from 2.7V to 20V supply while accurately sensing differential signals across −5V to 110V common-mode. With a 3.3V supply, the output swings from ~20mV to ~3.23V, maintaining full 50V/V gain and 1.1MHz bandwidth. This enables low-power, space-efficient monitoring of 48V infrastructure using standard logic-level ADCs. The INA296A3IDDFR's 2.5mA quiescent current further supports this use case.

What is the purpose of the NC pin (Pin 4) on the INA296A3IDDFR DDF package?

Pin 4 on the INA296A3IDDFR is designated NC (No Connect) but must be externally tied to GND per Texas Instruments' datasheet guidance. This connection stabilizes internal bias networks, reduces susceptibility to EMI, and ensures consistent startup behavior - especially critical in noisy 48V power environments. Leaving Pin 4 floating may cause output instability or increased offset drift. The requirement applies specifically to the DDF (SOT-23-8) variant; other packages (DGK, D) follow the same rule. Always connect NC to GND in all INA296A3IDDFR designs.

How does the INA296A3IDDFR's input bias current behave across its common-mode voltage range?

The INA296A3IDDFR features a unique input stage that holds input bias current constant at 35µA (typical) per input pin across the entire −5V to 110V common-mode range - unlike conventional high-voltage amplifiers where bias current scales with V_CM. This eliminates gain error variation due to shunt resistor loading, ensuring stable accuracy regardless of bus voltage. Measured data confirms <±5µA variation from −5V to 110V at 25°C, making the INA296A3IDDFR ideal for precision applications like BMS string current monitoring where leakage-induced error must be minimized.