Texas Instruments OPA2387DGKT

Overview

OPA2387DGKT from Texas Instruments is a dual-channel, ultra-high-precision zero-drift operational amplifier in an 8-pin VSSOP package. It delivers ±2 µV maximum input offset voltage, ±0.003 µV/°C drift, and 150 pA maximum input bias current across –40°C to +125°C, enabling stable DC-coupled signal conditioning for 24-bit ADC front-ends in weigh scales and temperature transmitters.

For engineers reviewing the OPA2387DGKT datasheet, OPA2387DGKT pinout, OPA2387DGKT application, or OPA2387DGKT equivalent, key selection criteria include its rail-to-rail input (±100 mV beyond rails), 5.7 MHz gain-bandwidth, 8.5 nV/√Hz broadband noise, and EMI-filtered inputs-critical for low-level sensor interfacing in industrial instrumentation and medical ventilators.

Technical Context

The OPA2387DGKT employs proprietary auto-zeroing with internal clocking (100–150 kHz) to continuously correct input offset and drift without introducing 1/f noise-verified by 177 nVPP (0.1 Hz to 10 Hz) and flat 8.5 nV/√Hz spectral density. Its input stage uses no antiparallel diodes, enabling true rail-to-rail common-mode operation with 115–150 dB CMRR.

It operates from 1.7 V to 5.5 V single supply or ±0.85 V to ±2.75 V dual supply, draws only 570 µA per amplifier, and maintains unity-gain stability while delivering 2.8 V/µs slew rate and 5.5 µs 0.01% settling time-optimized for precision analog input modules and semiconductor test equipment requiring long-term linearity.

Key Specifications

Pinout & Package

The OPA2387DGKT is housed in an 8-pin VSSOP (DGK) package with exposed thermal pad connected to V–. Pin 1 is OUT A; pin 2 is –IN A; pin 3 is +IN A; pin 4 is V–; pin 5 is +IN B; pin 6 is –IN B; pin 7 is OUT B; pin 8 is V+.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA2387DGKT, OPA2189IDGKT trades lower broadband noise for higher temperature-induced drift, while LTC2057HMS8#PBF offers superior supply rejection at double the quiescent power-making OPA2387DGKT optimal for wide-temperature, low-power, EMI-prone industrial sensor nodes.

Availability

OPA2387DGKT is available at Aetrix Electronics and suitable for electronic thermometer, weigh scale, and temperature transmitter applications requiring stable component supply, long-term calibration integrity, and industrial temperature range support.

Supply support for OPA2387DGKT 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 OPAx387 product line was designed specifically for ultra-stable, low-drift DC signal conditioning in high-resolution data acquisition, medical instrumentation, and industrial process control-where offset, drift, and noise directly limit measurement fidelity.

FAQ

What is the maximum input bias current specification for OPA2387DGKT over temperature?

The OPA2387DGKT has a maximum input bias current of ±200 pA across the full industrial temperature range of –40°C to +125°C, as specified in the Electrical Characteristics table. This value reflects worst-case manufacturing test limits and ensures reliable operation in high-impedance sensor interfaces such as thermistor or pH electrode circuits without significant leakage-induced errors. The OPA2387DGKT maintains this tight bound due to its zero-drift architecture and input-stage design.

Does OPA2387DGKT support rail-to-rail input operation beyond the supply rails?

Yes, the OPA2387DGKT supports common-mode input voltage ranges extending 100 mV beyond both supply rails-specifically (V–) – 0.1 V to (V+) + 0.1 V at 1.7 V supply and (V–) – 0.2 V to (V+) + 0.1 V at 5.5 V supply. This capability enables direct interfacing with sensors operating at ground or VCC without level-shifting circuitry. The OPA2387DGKT achieves this without input crossover distortion, preserving linearity across the extended range.

What is the gain-bandwidth product and unity-gain stability status of OPA2387DGKT?

The OPA2387DGKT has a guaranteed gain-bandwidth product of 5.7 MHz and is explicitly unity-gain stable, as confirmed in Section 7.1 and Table 6-7 of the datasheet. This allows robust closed-loop configurations down to gain = +1 without external compensation. The OPA2387DGKT maintains phase margin ≥40° with 100 pF capacitive load at unity gain, supporting direct driving of ADC input capacitors or cables in precision DAQ systems.

How does the zero-drift architecture of OPA2387DGKT eliminate 1/f noise?

The OPA2387DGKT uses an internal auto-zeroing architecture with a 100–150 kHz clock to periodically measure and cancel input offset voltage in real time. This continuous correction eliminates the low-frequency 1/f noise component, resulting in flat 8.5 nV/√Hz voltage noise density from 1 Hz upward and only 177 nVPP integrated noise from 0.1 Hz to 10 Hz. The OPA2387DGKT's lack of 1/f noise ensures stable baseline performance in DC-coupled applications like pressure transmitters where long-term drift must be minimized.

What thermal considerations apply to the OPA2387DGKT in VSSOP-8 (DGK) package?

The OPA2387DGKT in DGK package has a junction-to-board thermal resistance (RθJB) of 87 °C/W and requires the exposed thermal pad to be soldered to a PCB copper plane connected to V– for optimal heat dissipation. With 570 µA per amplifier at 5.5 V, total power dissipation is ~6.3 mW; however, ambient temperature rise must be limited to maintain operation within –40°C to +125°C. The OPA2387DGKT's RθJA of 165 °C/W means board layout significantly impacts thermal performance-thermal vias under the pad are strongly recommended.