Texas Instruments OPA2677U

Overview

OPA2677U from Texas Instruments is a dual, wideband, high-output-current current-feedback operational amplifier designed for demanding line driver applications. It delivers ±500mA output current, 200MHz bandwidth at G=+4, 1800V/µs slew rate, and ±5V output swing on ±6V supplies-enabling xDSL and broadband video line driving with low harmonic distortion.

For engineers reviewing the OPA2677U datasheet, OPA2677U pinout, OPA2677U application, or OPA2677U equivalent, key selection criteria include its current-feedback architecture, thermal performance in SO-8 package (θ_JA = 125°C/W), minimum 380mA guaranteed output current at +25°C, and compatibility with single +5V or dual ±6V supply rails.

Technical Context

The OPA2677U operates as a current-feedback op amp, where bandwidth and distortion remain stable across gain settings due to feedback resistor (RF)-dominated transimpedance loop control. Its output stage supports high-current sourcing (+1.2A peak) and sinking (–1.6A peak) while maintaining < –85dBc 2nd-harmonic distortion at 5MHz into 100Ω under ADSL upstream conditions.

Specified over –40°C to +85°C, it features rail-swing capability within 1V of either supply, input common-mode range of ±4.5V (min), and CMRR ≥55dB at 25°C-making it suitable for differential I/Q channel amplification and composite video driving with <0.1%/0.1° dG/dφ nonlinearity into 10×15Ω loads.

Key Specifications

Pinout & Package

OPA2677U is housed in an SO-8 package (Package Code: D) with exposed pad not present; thermal management relies on standard PCB copper pour. Pin functions are validated per TI SBOS126I Rev I datasheet Figure: "OPA2677U, DDA" top view.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA2691 and THS6042, the OPA2677U uniquely balances 200MHz bandwidth, ±380mA guaranteed output, and +5V single-supply operation-making it the only TI dual CFB op amp qualified for ADSL CPE line driver compliance without external boost stages.

Availability

OPA2677U is available at Aetrix Electronics and suitable for xDSL line driver, broadband video distribution, and matched I/Q channel amplifier applications requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for OPA2677U 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 company headquartered in Dallas, Texas, specializing in analog and embedded processing technologies with over 50 years of op amp innovation.

The OPA2677U belongs to TI's high-speed current-feedback op amp product line, engineered specifically for broadband communications infrastructure where high output current, low distortion, and supply flexibility are critical.

FAQ

What is the maximum continuous output current specification for OPA2677U at +85°C?

The OPA2677U guarantees ±320mA minimum continuous output current at +85°C under ±6V supply conditions, as specified in the Electrical Characteristics table (DC PERFORMANCE section, "Current Output" row). This derating from the +25°C minimum of ±380mA reflects thermal limits of the SO-8 package; sustained operation above this level requires careful thermal design or reduced ambient temperature. The OPA2677U datasheet confirms this value is tested and characterized across temperature.

Can OPA2677U operate from a single +5V supply, and what output swing is achievable?

Yes, the OPA2677U supports single +5V operation with a typical output swing of ±2.5V (5VPP) into high-impedance loads, and ≥3.5VPP into 100Ω loads per the +5V Electrical Characteristics table. It achieves >100MHz bandwidth at G=+4 under this condition, enabled by input common-mode range extending to within 1.3V of either rail and output swing to within 1V of each supply. The OPA2677U application circuit in Figure 3 validates this configuration.

Is OPA2677U unity-gain stable, and what is its small-signal bandwidth at G = +1?

Yes, the OPA2677U is unity-gain stable with a small-signal bandwidth of 220MHz at G = +1 (RF = 511Ω), as confirmed in the AC PERFORMANCE table under ±6V conditions. This bandwidth remains stable across temperature (≥165MHz at +85°C) and is measured with 0.5VPP output. The OPA2677U datasheet explicitly states "UNITY-GAIN STABLE: 220MHz (G = +1)" in its FEATURES list.

What is the thermal resistance (θ_JA) of the OPA2677U in its SO-8 package?

The OPA2677U in SO-8 package (orderable part number OPA2677U) has a junction-to-ambient thermal resistance (θ_JA) of 125°C/W, as specified in the THERMAL CHARACTERISTICS table for package U. This value assumes standard JEDEC 2-layer board conditions; improved copper pour can reduce effective θ_JA, but the 125°C/W rating is used for worst-case thermal design. The OPA2677U datasheet lists this parameter under "Thermal Resistance, θ_JA".

Does OPA2677U require external compensation components for stability in G = +4 configuration?

No, the OPA2677U does not require external compensation in standard G = +4 configurations; stability is ensured by internal compensation and proper RF selection (402Ω for ±6V, 453Ω for +5V). The datasheet specifies these exact resistor values in Figures 1 and 3, and notes that bandwidth flatness and pulse response meet specifications without added components. External RS series resistors are recommended only for capacitive loads >10pF, per the "RECOMMENDED RS vs CAPACITIVE LOAD" curves.