Texas Instruments BUF634TG3

Overview

BUF634TG3 from Texas Instruments is a high-speed, unity-gain, open-loop buffer IC designed for current-boosting and capacitive load driving in precision analog signal paths. It delivers 250mA continuous output current, 2000V/µs slew rate, 30–180MHz pin-selectable bandwidth, ±2.25V to ±18V supply range, and internal thermal shutdown - enabling robust valve, solenoid, and video driver implementations.

For engineers reviewing the BUF634TG3 datasheet, BUF634TG3 pinout, BUF634TG3 application, or BUF634TG3 equivalent, key selection criteria include its adjustable bandwidth via external resistor, low-quiescent-current mode (1.5mA), open-loop architecture for op amp output stage augmentation, and TO-263-5 surface-mount power package with integrated thermal protection.

Technical Context

The BUF634TG3 implements an open-loop complementary follower topology with externally configurable gain-bandwidth trade-off via the BW pin connected to V– through a resistor. Its dual operating modes - low-quiescent-current (1.5mA, 30MHz) and wide-bandwidth (15mA, 180MHz) - are determined by that resistor value and are validated across TO-220 and TO-263 packages.

Thermal shutdown activates at 175°C junction temperature, and internal current limiting caps short-circuit output at ±350–±550mA depending on mode. Input impedance exceeds 1400MΩ || 5pF in low-IQ mode, while output headroom remains ≤2.5V from rails at ±150mA load - critical for high-fidelity line and video drivers.

Key Specifications

Pinout & Package

BUF634TG3 is supplied in a 5-pin TO-263 (KTT) surface-mount plastic power package with exposed thermal pad for enhanced heat dissipation. Package dimensions: 10.16mm × 15.24mm (L × W), compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar unity-gain, high-current buffer applications.

Compared with BUF634TG3, BUF634A offers superior speed but less power efficiency, while LMH6321 trades bandwidth adjustability for precision current limiting and lower noise - making BUF634TG3 optimal for cost-sensitive, thermally constrained, or bandwidth-tunable industrial drivers.

Availability

BUF634TG3 is available at Aetrix Electronics and suitable for valve driver, solenoid driver, and ATE pin driver applications requiring stable component supply, long-term industrial lifecycle support, and consistent TO-263 packaging.

Supply support for BUF634TG3 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 high-performance amplifier design and industrial-grade reliability.

The BUF634 product line was engineered specifically for high-current, high-speed analog signal buffering - targeting applications where op amps require output stage augmentation without compromising stability or thermal performance.

FAQ

What is the function of the BW pin on the BUF634TG3?

The BW pin on the BUF634TG3 sets bandwidth and quiescent current by connecting it to V– via an external resistor. A high resistance yields low IQ (1.5mA, 30MHz); low resistance increases IQ to 15mA and bandwidth to 180MHz. This resistor-based configuration avoids firmware or digital interface complexity while enabling precise analog tuning of the BUF634TG3's performance envelope.

Can the BUF634TG3 be used inside the feedback loop of an op amp?

Yes, the BUF634TG3 is explicitly recommended for insertion inside the feedback loop of operational amplifiers to increase output current capability, eliminate thermal feedback effects, and improve capacitive load drive. Its unity-gain, open-loop architecture ensures stability when placed in series with the op amp output, and its 250mA drive sustains performance where the op amp alone would saturate or oscillate.

What thermal protection features does the BUF634TG3 include?

The BUF634TG3 integrates thermal shutdown that disables the output when junction temperature reaches 175°C, preventing irreversible damage during overload or poor heatsinking. It also includes internal current limiting that caps short-circuit output at ±350–±550mA depending on operating mode. These protections are active across the full –40°C to +125°C ambient range and do not require external circuitry - enhancing system robustness in the BUF634TG3's target industrial applications.

Does the BUF634TG3 require external compensation components?

No, the BUF634TG3 is internally compensated and requires no external capacitors or resistors for stability. Its open-loop complementary follower design is inherently stable across all specified loads (including 100Ω and 150pF), and its bandwidth is adjusted solely via the BW-to-V– resistor. This simplifies layout, reduces BOM count, and eliminates tuning iterations - a key advantage of the BUF634TG3 in time-constrained development cycles.

What is the maximum output voltage swing of the BUF634TG3 at ±15V supplies?

At ±15V supplies and ±150mA load, the BUF634TG3 delivers a minimum output voltage swing of (V+) – 4V for sourcing and (V–) + 5V for sinking - i.e., +11V to –10V. This 21V total swing maintains linearity and low distortion in demanding applications like video and ATE drivers, and is validated across temperature for both low-IQ and wide-bandwidth modes of the BUF634TG3.