Texas Instruments OPA640P

Overview

OPA640P from Burr-Brown (now Texas Instruments) is a unity-gain stable, wideband voltage-feedback operational amplifier with 1.3GHz gain-bandwidth product, 350V/µs slew rate, and 2.9nV/√Hz input voltage noise density at 1MHz–500MHz. It features fully symmetrical differential inputs, 85dB common-mode rejection, and is optimized for high-resolution video, ADC/DAC gain stages, and RF signal conditioning.

For engineers reviewing the OPA640P datasheet, OPA640P pinout, OPA640P application, or OPA640P equivalent, this page delivers verified electrical specifications, package-specific layout guidance, real-world settling time behavior (22ns to 0.01%), differential gain/phase performance at 3.58MHz, and validated alternatives for high-speed precision analog design.

Technical Context

The OPA640P employs a classical voltage-feedback architecture-not current-feedback-enabling true differential input symmetry, predictable AC response, and compatibility with standard op amp configurations including inverting, non-inverting, active filters, and differential amplifiers. Its internal compensation ensures unity-gain stability without external components.

It operates from ±4.5V to ±5.5V supplies, delivers ±2.25V output swing into 100Ω, achieves 75dBc spurious-free dynamic range at 10MHz, and maintains <0.07% differential gain error and <0.008° differential phase error at NTSC subcarrier frequency-critical for broadcast-quality video signal chains.

Key Specifications

Pinout & Package

OPA640P is housed in an 8-pin plastic DIP (dual in-line package) with 0.3-inch body width and through-hole mounting. Thermal resistance θ_JA is 100°C/W. All four power supply pins must be used for optimal distortion performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar wideband voltage-feedback amplifier applications.

Compared with OPA640P, LMH6629MA/NOPB trades lower noise for greater bandwidth and less robust unity-gain stability, while THS3201D sacrifices DC precision and settling speed for raw small-signal bandwidth-making OPA640P the sole choice for mixed-signal, DC-coupled, video/communications applications demanding both speed and fidelity.

Availability

OPA640P is available at Aetrix Electronics and suitable for communications infrastructure, medical imaging front-ends, and test & measurement equipment requiring stable component supply across extended temperature ranges (–40°C to +85°C) and long-lifecycle production programs.

Supply support for OPA640P 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

Burr-Brown Corporation, acquired by Texas Instruments in 2000, specialized in high-precision analog ICs for instrumentation, medical, and communications systems before integration into TI's precision analog portfolio.

The OPA640P belongs to Burr-Brown's OPA6xx family of ultra-high-speed voltage-feedback op amps, designed specifically for DC-coupled, low-distortion signal conditioning in video, RF, and high-speed data acquisition systems.

FAQ

What is the maximum capacitive load the OPA640P can drive without instability?

The OPA640P is characterized for 2pF capacitive load in unity-gain configuration. Driving larger capacitive loads-such as ADC input capacitance-requires series isolation resistance (5Ω–25Ω) between the OPA640P output and the load to maintain phase margin. Without this resistor, loads >2pF may cause peaking or oscillation, especially in the DIP package due to higher parasitic inductance.

Does the OPA640P require external offset nulling for precision DC applications?

No-OPA640P has ±2.0mV max input offset voltage and ±10µV/°C drift, sufficient for most high-speed DC-coupled applications. External trim is optional and only recommended if sub-millivolt offset is required; Figure 1 in the datasheet shows a temperature-stable trim circuit using 47kΩ and 20kΩ resistors that avoids degrading drift performance.

Can the OPA640P be operated from a single +10V supply?

No-the OPA640P is specified only for split supplies from ±4.5V to ±5.5V. Operation from +10V alone violates absolute maximum ratings: the differential input voltage limit is ±1.2V, and input common-mode range is limited to ±2.85V. Using single-supply configurations risks permanent damage or parametric failure.

Why does the OPA640P datasheet emphasize using all four power supply pins?

Using both +VS1/+VS2 and –VS1/–VS2 reduces effective supply impedance seen by input and output stages, lowering distortion by up to 10dB at 10MHz. The DIP package's lead inductance makes this critical-omitting either +VS2 or –VS2 increases harmonic content and degrades SFDR, particularly in unity-gain buffers driving reactive loads.

Is the OPA640P pin-compatible with newer TI op amps like the OPA657?

No-OPA640P uses an 8-pin DIP footprint with specific pin assignments (e.g., Pin 8 = NC), while OPA657 uses SO-8 or SOT-23 packages with different pinouts and no NC pin. Functionally, OPA657 offers higher 1.6GHz GBW but lacks the OPA640P's differential gain/phase specs and DIP thermal performance-direct replacement is not feasible without PCB redesign.