Texas Instruments THS4275DRBT

Overview

THS4275DRBT from Texas Instruments is a low-noise, high-slew-rate, unity-gain-stable voltage-feedback amplifier with power-down functionality. It delivers 1.4 GHz small-signal bandwidth (±5 V), –92 dBc THD at 30 MHz, 3 nV/√Hz input voltage noise, and 1000 V/μs slew rate. It operates from ±5 V or single 5–10 V supplies and serves as a high-linearity ADC preamplifier in RF receiver signal chains.

For engineers reviewing the THS4275DRBT datasheet, THS4275DRBT pinout, THS4275DRBT application, or THS4275DRBT equivalent, key selection criteria include its power-down enable threshold (REF ±1.0 V / REF ±1.7 V), junction-temperature-limited oscillation ceiling (+60°C), and MSOP-8 PowerPAD™ thermal performance requiring PCB thermal plane connection.

Technical Context

The THS4275DRBT uses a voltage-feedback architecture optimized for wideband, low-distortion operation across gain configurations from –1 to +10. Its internal compensation ensures unity-gain stability without external phase compensation networks, eliminating stability concerns common in decompensated amplifiers.

Power-down control is implemented via a dedicated PD pin referenced to either VS– or VS+, enabling fast 4 μs turn-on and 3 μs turn-off transitions while reducing quiescent current to ≤1.2 mA. The device's thermal design requires soldering the exposed PowerPAD™ to a thermally conductive PCB plane to maintain TJ ≤ +60°C and prevent low-level oscillation.

Key Specifications

Pinout & Package

THS4275DRBT is housed in an 8-pin leadless MSOP package with PowerPAD™ (DRB), requiring thermal connection of the exposed die paddle to a PCB copper plane for reliable operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed amplifier applications.

Compared with THS4271DRBT, THS4275DRBT adds power-down control at identical bandwidth and distortion performance, while LMH6629MF/NOPB trades off power-down and wideband linearity for lower noise in narrower-band applications.

Availability

THS4275DRBT is available at Aetrix Electronics and suitable for high-speed data acquisition, wireless infrastructure transceivers, and precision video signal conditioning requiring stable component supply and guaranteed long-term manufacturability.

Supply support for THS4275DRBT 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 manufacturing.

The THS427x family was engineered for demanding wideband signal chain applications including ADC/DAC interfacing, communications infrastructure, and test equipment-prioritizing unity-gain stability, low distortion, and thermal robustness.

FAQ

What is the maximum junction temperature for stable operation of the THS4275DRBT?

The THS4275DRBT must be operated with a maximum die temperature of +60°C to prevent low-level oscillation. This requires proper thermal design: the PowerPAD™ must be soldered to a PCB thermal plane, and ambient temperature plus power dissipation must be modeled to ensure TJ remains ≤+60°C. Exceeding this limit risks instability even if case temperature appears acceptable.

How does the power-down function of the THS4275DRBT work, and what are its timing characteristics?

The THS4275DRBT enters power-down mode when the PD pin voltage crosses reference-based thresholds: enable occurs at REF +1.0 V (REF = 0 V or VS–), disable at REF –1.7 V (REF = VS+ or floating). Turn-on delay is 4 μs and turn-off delay is 3 μs to 50% of final supply current. During power-down, quiescent current drops to ≤1.2 mA, and output impedance rises to 200 kΩ.

Can the THS4275DRBT operate from a single 5-V supply, and how does performance compare to ±5-V operation?

Yes, THS4275DRBT supports single 5–10 V operation. At VS = 5 V, small-signal bandwidth drops to 1.2 GHz (vs. 1.4 GHz at ±5 V), slew rate decreases to 750 V/μs, and THD degrades to –75 dBc at 30 MHz. Input common-mode range narrows to 1.3–3.7 V, requiring careful level-shifting for DC-coupled inputs. Performance remains excellent for many applications but is measurably reduced versus dual-supply operation.

What is the role of the REF pin on the THS4275DRBT, and how should it be connected?

The REF pin on the THS4275DRBT establishes the reference voltage for interpreting the PD pin logic thresholds. It can be tied to VS– (0 V in single-supply mode) or left floating (for VS+-referenced thresholds). When REF = 0 V, PD > +1.0 V enables normal operation; when REF = VS+, PD < VS+ –1.7 V disables the amplifier. REF must not be left unterminated in noisy environments to avoid erratic power-down behavior.

Is the THS4275DRBT pin-compatible with the THS4271DRBT, and what design changes are needed for substitution?

THS4275DRBT and THS4271DRBT share identical pinouts and footprints in the DRB package, but pin functions differ: THS4275DRBT uses Pin 1 as REF and Pin 5 as PD, whereas THS4271DRBT uses both as NC. Substituting THS4275DRBT for THS4271DRBT requires adding REF and PD circuitry (pull-up/down resistors, logic control); substituting THS4271DRBT for THS4275DRBT requires grounding Pins 1 and 5. Thermal and decoupling design remains identical.