Texas Instruments INA2126P

Overview

INA2126P from Texas Instruments is a dual-channel, micropower instrumentation amplifier designed for precision differential signal acquisition in low-power industrial and medical systems. It delivers 175 μA/channel quiescent current, ±1.35V to ±18V dual-supply operation, 250 μV max input offset voltage, 3 μV/°C max offset drift, and 35 nV/√Hz input voltage noise - enabling high-accuracy sensor interfacing in battery-powered ECG monitors and flow transmitters.

For engineers reviewing the INA2126P datasheet, INA2126P pinout, INA2126P application, or INA2126P equivalent, this page provides verified package mapping (16-pin PDIP, N package), dual-amplifier functional partitioning, gain-setting resistor interface (RG = 3–80 kΩ for G = 5–10,000), and confirmed channel separation >130 dB at DC - all critical for layout-sensitive, low-drift analog front-end designs.

Technical Context

The INA2126P implements a two-op-amp topology with separate internal feedback paths for each channel (SenseA/SenseB), enabling independent gain configuration and load-referred output sensing. Its input stage features balanced, high-impedance (≥1 GΩ) FET inputs with laser-trimmed 40 kΩ/10 kΩ internal resistor networks that define the gain equation G = 5 + 80 kΩ/RG.

Each channel operates with fully decoupled bias circuitry, delivering >130 dB DC channel separation and supporting simultaneous differential measurements without crosstalk-induced error. The REF pins (RefA/RefB) accept low-impedance reference voltages to level-shift outputs - essential for single-supply operation and ratiometric sensor interfaces.

Key Specifications

Pinout & Package

INA2126P is housed in a 16-pin plastic dual in-line package (PDIP, N package) with 0.300-inch body width and through-hole mounting. Thermal resistance R_θJA = 39.3°C/W enables operation up to +85°C ambient without forced airflow.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel instrumentation amplifier applications.

Compared with INA2126P, INA2128P trades higher quiescent current for tighter offset specs, while AD8226ARZ reduces channel count and package size at the expense of independent reference control and channel isolation - making INA2126P optimal for space-constrained dual-sensor systems requiring balanced performance across power, precision, and configurability.

Availability

INA2126P is available at Aetrix Electronics and suitable for ECG monitors, industrial flow transmitters, multiparameter patient monitors, and AC charging pile sensor hubs requiring stable component supply across extended product lifecycles.

Supply support for INA2126P 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 chain components.

The INAx126 family was engineered for low-power, high-accuracy sensor signal conditioning in portable and industrial instrumentation - emphasizing micropower operation, laser-trimmed gain accuracy, and dual-channel independence without performance compromise.

FAQ

What is the maximum gain achievable with INA2126P and how is it set?

The INA2126P supports gains from 5 V/V to 10,000 V/V using a single external resistor (RG) connected between its dedicated gain pins. For the INA2126P, gain is calculated as G = 5 + 80 kΩ/RG. To achieve G = 10,000, RG must be 8.0 Ω - requiring careful layout to minimize parasitic resistance. The INA2126P datasheet confirms this relationship applies identically to both channels, with Pin 3–4 setting Channel A gain and Pin 13–14 setting Channel B gain.

Does INA2126P support single-supply operation, and what design considerations apply?

Yes, the INA2126P operates from a single supply of 2.7 V to 36 V. Critical design requirements include driving RefA and RefB with a low-impedance mid-supply voltage (e.g., V_CC/2) to prevent output saturation, ensuring input common-mode voltage stays within (V−) + 0.5 V to (V+) − 0.5 V, and using decoupling capacitors on V+ and V− pins. The INA2126P's two-op-amp architecture maintains full functionality in single-supply mode without external level-shifting circuitry.

How does the SenseA and SenseB functionality improve measurement accuracy in INA2126P?

SenseA (Pin 7) and SenseB (Pin 10) provide Kelvin feedback connections that sense output voltage directly at the load, compensating for voltage drops across PCB traces or connectors. When SenseA is connected to VOA (Pin 6) and SenseB to VOB (Pin 11), the INA2126P maintains specified gain accuracy and linearity even with 100 mΩ series resistance. This feature is unique to the dual-channel INA2126P and absent in single-channel variants like INA126P.

What is the guaranteed channel separation for INA2126P and why does it matter?

The INA2126P guarantees ≥130 dB channel separation at DC, verified in the official datasheet under "Electrical Characteristics." This means less than 1 μV of signal from Channel A appears at Channel B's output when amplifying 1 V signals - essential for simultaneous acquisition of unrelated physiological signals (e.g., ECG + respiration) or isolated current/voltage measurements in AC charging piles without cross-talk corruption.

Can INA2126P replace INA126P in existing designs, and what changes are required?

No, the INA2126P cannot directly replace the INA126P due to fundamental differences: INA2126P is dual-channel in a 16-pin PDIP (N), while INA126P is single-channel in an 8-pin PDIP (P). Pinouts, gain-setting configurations (two RG pairs vs. one), and reference/sense structures are incompatible. Migration requires PCB redesign, new layout for dual-channel routing, and verification of thermal dissipation (R_θJA = 39.3°C/W vs. 52.2°C/W for INA126P).