Texas Instruments OPA209AIDR

Overview

OPA209AIDR from Texas Instruments is a single-channel, precision, low-noise operational amplifier in an 8-pin SOIC package. It delivers 2.2 nV/√Hz voltage noise at 1 kHz, 130 nVPP 0.1-Hz to 10-Hz noise, and 18 MHz gain bandwidth while consuming only 2.5 mA per channel - enabling high-fidelity signal conditioning in battery-powered instrumentation and precision data acquisition systems.

For engineers reviewing the OPA209AIDR datasheet, OPA209AIDR pinout, OPA209AIDR application, or OPA209AIDR equivalent, key selection criteria include its rail-to-rail output swing, ±2.25 V to ±18 V dual-supply operation, 150 µV max input offset, and verified performance across –40°C to 125°C for industrial and medical sensor front-ends.

Technical Context

The OPA209AIDR employs a SiGe bipolar process to achieve unity-gain stability without phase reversal, supporting fast settling (2.6 µs to 16-bit accuracy for 10-V step) and robust 6.4 V/µs slew rate. Its input stage features back-to-back diode protection and operates with common-mode range from (V–) + 1.5 V to (V+) – 1.5 V.

It maintains 120 dB minimum CMRR and PSRR over –40°C to 125°C, with open-loop gain >120 dB at 25°C and >110 dB across full temperature range - critical for high-precision DC-coupled amplification in PLL loop filters and ADC driver stages.

Key Specifications

Pinout & Package

OPA209AIDR is housed in an 8-pin SOIC (D package), body size 4.90 mm × 3.91 mm, with JEDEC MS-012AC standard footprint and 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision op amp applications.

Compared with OPA211AIDR and OPA189AIDR, the OPA209AIDR uniquely balances ultra-low broadband noise, 18 MHz bandwidth, and 2.5 mA quiescent current - making it optimal for high-resolution, moderate-bandwidth industrial data acquisition where thermal and power constraints coexist.

Availability

OPA209AIDR is available at Aetrix Electronics and suitable for precision instrumentation, medical diagnostics, and industrial automation requiring stable component supply with extended temperature support (–40°C to 125°C), low-noise performance, and SOIC package compatibility.

Supply support for OPA209AIDR 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 amplifiers and signal chain solutions.

The OPA209 series was designed for high-fidelity, low-power signal conditioning in demanding industrial, medical, and test equipment - prioritizing noise performance, DC accuracy, and thermal robustness over raw speed.

FAQ

What is the maximum supply voltage rating for the OPA209AIDR?

The OPA209AIDR has an absolute maximum supply voltage of 40 V total (i.e., V+ – V– ≤ 40 V). Operation beyond this risks permanent damage. The recommended operating range is ±2.25 V to ±18 V dual supply or 4.5 V to 36 V single supply. TI specifies performance across this full range, with thermal derating required above 125°C junction temperature. Always observe the 0.1 µF local decoupling on both V+ and V– pins per the OPA209AIDR datasheet.

Does the OPA209AIDR support rail-to-rail input operation?

No, the OPA209AIDR does not support rail-to-rail input. Its common-mode input voltage range is specified as (V–) + 1.5 V to (V+) – 1.5 V - a 3-V exclusion zone near each rail. This limitation arises from its bipolar input stage. For true rail-to-rail input, consider alternatives like the OPA188 or OPA192. However, the OPA209AIDR's rail-to-rail output swing (within 0.2 V of rails at 10 kΩ) remains fully functional and is explicitly validated in the datasheet.

What is the typical 0.1-Hz to 10-Hz noise performance of the OPA209AIDR?

The OPA209AIDR delivers 130 nVPP typical 0.1-Hz to 10-Hz noise, with a maximum of 180 nVPP across temperature and process variation. This value is measured under standard conditions: VS = ±15 V, RL = 10 kΩ to midsupply, and VCM = VOUT = midsupply. Its low 1/f noise corner (<10 Hz) makes it especially effective in DC-coupled, low-frequency applications such as precision weigh scales and thermocouple amplifiers where long-term stability is critical.

Can the OPA209AIDR drive capacitive loads without oscillation?

Yes, the OPA209AIDR is unity-gain stable and can safely drive ≥100 pF capacitive loads without external compensation, as confirmed by Figure 30 in the datasheet showing <10% overshoot up to 1000 pF. For loads >100 pF, TI recommends adding a small series resistor (e.g., 10–50 Ω) between the output and capacitance to isolate the reactive load from the op amp's output stage - preserving phase margin and preventing peaking. This technique is widely used in ADC driver and active filter designs using the OPA209AIDR.

Is the OPA209AIDR pin-compatible with other members of the OPAx209 family?

No, the OPA209AIDR (single, 8-pin SOIC) is not pin-compatible with the dual OPA2209 or quad OPA4209. While all share identical pin functions per channel, the OPA209AIDR uses pins 5–7 as NC (no connect), whereas OPA2209 repurposes those pins for second-channel I/O. Substituting OPA209AIDR for OPA2209 in a dual-channel layout will result in incorrect connectivity and functional failure. Always verify package-specific pin mapping - the OPA209AIDR pinout is defined exclusively for the D (SOIC-8) package in the datasheet.