Texas Instruments INA156EA/2K5

Overview

INA156EA/2K5 from Texas Instruments (formerly Burr-Brown) is a single-supply, rail-to-rail output CMOS instrumentation amplifier with fixed gain options of 10V/V or 50V/V, ±5µV/°C offset drift, 550kHz bandwidth at G=10, and operation from +2.7V to +5.5V - designed for precision sensor signal conditioning in industrial and medical systems.

For engineers reviewing the INA156EA/2K5 datasheet, INA156EA/2K5 pinout, INA156EA/2K5 application, or INA156EA/2K5 equivalent, this page delivers verified specifications, MSOP-8 package details, gain configuration logic, rail-to-rail output behavior, and real-world use cases including bridge sensor amplification and A/D converter driving - all grounded in the official SBOS119 datasheet and TI packaging documentation.

Technical Context

The INA156EA/2K5 implements a two-op-amp CMOS instrumentation architecture with internal laser-trimmed thin-film resistors defining fixed gains of 10V/V (RG pins open) or 50V/V (RG pins shorted). Its rail-to-rail output stage uses complementary common-source transistors enabling 20mV swing from rails under 10kΩ load.

Input bias current is ≤10pA across –55°C to +125°C, supporting high-impedance sources like thermocouples and piezoelectric sensors. Gain error is ±0.4% (G=10) or ±0.8% (G=50), with CMRR reaching 87dB at G=50 and 10Hz–10kHz frequencies - critical for rejecting noise in low-level differential measurements.

Key Specifications

Pinout & Package

INA156EA/2K5 is housed in an 8-pin VSSOP (DGK) package - identical in footprint and pinout to MSOP-8 - with thermal resistance θ_JA = 150°C/W and moisture sensitivity level MSL-2 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8226ARMZ and INA333AIDRGT, the INA156EA/2K5 delivers optimal balance of fixed-gain simplicity, rail-to-rail output, –55°C to +125°C qualification, and VSSOP-8 footprint - making it the most cost-effective choice for production bridge and biopotential amplifiers requiring no gain tuning.

Availability

INA156EA/2K5 is available at Aetrix Electronics and suitable for industrial sensor amplification, medical biopotential acquisition, A/D converter driving, and PCMCIA data acquisition requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for INA156EA/2K5 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 acquired Burr-Brown in 2000 and maintains its precision analog portfolio with rigorous qualification standards, global manufacturing, and long-term product lifecycle commitments.

The INA156 series was designed specifically for low-voltage, single-supply instrumentation tasks - emphasizing rail-to-rail output, low drift, and fixed-gain reliability in harsh environments from factory floors to patient bedsides.

FAQ

What gain options does the INA156EA/2K5 support, and how are they configured?

The INA156EA/2K5 supports two fixed gain options: 10V/V and 50V/V. Gain is selected by the state of pins 1 and 8 - left open for G=10, shorted together for G=50. No external resistors are needed for these configurations, and gain error remains ≤±0.4% (G=10) or ≤±0.8% (G=50) across temperature. The INA156EA/2K5 datasheet confirms this pin-strapping method eliminates resistor matching errors and improves long-term stability versus discrete gain networks.

Does the INA156EA/2K5 support true rail-to-rail input common-mode range?

No - the INA156EA/2K5 features rail-to-rail *output* swing (within 20mV of rails), but its input common-mode range is limited. At VS=5.5V, VCM spans 0.3V to 5.2V; at VS=2.7V, it narrows to 0.2V to 2.5V. Operation near (V+) – 1.8V causes degraded CMRR and offset shift, as documented in Figure 6 of the INA156EA/2K5 datasheet. For full rail-to-rail input, consider zero-drift alternatives like INA333.

Can the INA156EA/2K5 drive capacitive loads such as ADC inputs directly?

Yes - the INA156EA/2K5 is stable driving ≥100pF loads, as verified in typical performance curves (Figure 13). Its 6.5V/µs slew rate and fast settling (5µs to 0.1% at G=10) enable direct interface to SAR ADCs like ADS7818 without external isolation. However, overshoot increases above 1nF; for >500pF, add a 10Ω series resistor per the INA156EA/2K5 application note on capacitive loading.

What is the maximum operating temperature range for the INA156EA/2K5?

The INA156EA/2K5 is fully specified from –55°C to +125°C, with absolute maximum ratings extending to –65°C to +150°C for storage and junction. This extended range is validated per TI's packaging documentation (DGK package, MSL-2), making the INA156EA/2K5 suitable for under-hood automotive, downhole oil/gas, and military applications where commercial-grade parts fail.

How does the reference input (Ref) affect system performance in the INA156EA/2K5?

The Ref pin sets the output DC offset: VO = (VIN+ – VIN–) × G + VREF. It must be driven by a low-impedance source (<20Ω) to maintain gain accuracy - a 20Ω impedance causes 0.2% gain error at G=50. In single-supply systems, tying Ref to VS/2 centers the output swing; for ADC interfacing, Ref can be set to match the ADC's reference voltage. This behavior is explicitly characterized in the INA156EA/2K5 datasheet Section "Applications Information".