Texas Instruments THS4031IDG4

Overview

THS4031IDG4 from Texas Instruments is a single-channel, ultra-low-noise (1.2nV/√Hz), high-speed voltage-feedback operational amplifier with 100MHz bandwidth (G = 2, –3dB), 100V/μs slew rate, and offset nulling pins. It delivers 200mA output drive and operates from ±4.5V to ±16V supplies, serving as a precision buffer/driver for high-resolution SAR ADCs like ADS8422 in data acquisition systems.

For engineers reviewing the THS4031IDG4 datasheet, THS4031IDG4 pinout, THS4031IDG4 application, or THS4031IDG4 equivalent, key selection criteria include input voltage noise floor, distortion performance at 1MHz (–96dBc into 1kΩ), unity-gain stability, thermal pad handling in HVSSOP-8, and offset nulling capability for precision DC-coupled signal chains.

Technical Context

The THS4031IDG4 uses a 30V complementary bipolar process enabling GHz f_T transistors, delivering wide bandwidth and fast settling (70ns to 0.1%). Its voltage-feedback architecture supports stable operation at unity gain (120MHz bandwidth) and maintains low distortion across load conditions (RL = 150Ω or 1kΩ).

It features dedicated offset nulling pins (1 and 8) for trimming input offset voltage (typ. 0.3mV), and includes internal compensation optimized for speed-requiring external series isolation resistors (>20Ω) when driving capacitive loads >10pF to preserve phase margin and prevent ringing.

Key Specifications

Pinout & Package

THS4031IDG4 is packaged in an 8-pin HVSSOP (DGN) with exposed thermal pad. The package measures 3.0mm × 4.9mm and requires connection of the thermal pad to a large copper plane for optimal thermal performance (R_θJB = 33°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed, low-noise op-amp applications.

Compared with OPA656U and LMH6629MA, THS4031IDG4 uniquely balances ultra-low noise, high output current, and user-adjustable offset-making it optimal for DC-accurate, high-fidelity ADC interface and ultrasound receive applications where all three traits are simultaneously required.

Availability

THS4031IDG4 is available at Aetrix Electronics and suitable for high-speed data acquisition, medical ultrasound imaging, and broadcast video equipment requiring stable component supply and long-term production continuity.

Supply support for THS4031IDG4 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 innovation in high-performance op-amps and signal chain solutions.

The THS403x family was designed specifically for low-noise, high-bandwidth analog signal conditioning in communications, imaging, and precision measurement systems-emphasizing voltage-feedback speed, distortion control, and robust output drive.

FAQ

What is the maximum recommended capacitive load for stable operation of the THS4031IDG4?

The THS4031IDG4 requires external isolation for capacitive loads exceeding 10pF. A minimum 20Ω series resistor between the OUT pin and the load is recommended to maintain phase margin and prevent high-frequency oscillation or ringing. In 75Ω transmission systems, a 75Ω resistor provides both isolation and source impedance matching-ensuring stable operation while preserving signal integrity in video or RF applications.

Does the THS4031IDG4 support single-supply operation, and what is the minimum supply voltage?

Yes, the THS4031IDG4 supports single-supply operation with a minimum total supply voltage of 9V (e.g., 0V to +9V). Its input common-mode range extends to within 1.2V of each rail (±3.8V at ±5V supply), and output swing reaches ±3.4V into 1kΩ. For rail-to-rail input/output performance, external level-shifting or biasing is required-THS4031IDG4 is not a rail-to-rail device.

How does the offset nulling function work on the THS4031IDG4, and what components are needed?

The THS4031IDG4 provides offset nulling via pins 1 and 8. A 10kΩ potentiometer is connected between these pins, with its wiper tied to VCC–. Adjusting the potentiometer changes the internal current balance in the input stage, reducing input offset voltage to <100μV. This circuit is essential for DC-coupled applications demanding sub-millivolt accuracy-such as precision sensor interfaces or calibration-grade instrumentation using THS4031IDG4.

What thermal considerations apply to the THS4031IDG4 in HVSSOP-8 (DGN) package?

The THS4031IDG4 in DGN package features an exposed thermal pad that must be soldered to a large PCB copper plane for effective heat dissipation. With R_θJB = 33°C/W, proper thermal pad connection reduces junction temperature rise significantly. Without it, R_θJA degrades to 60.7°C/W-risking thermal shutdown or accelerated aging under sustained 200mA output current. TI recommends minimum 200mm² copper area with multiple thermal vias to internal ground planes.

Can the THS4031IDG4 drive a 150Ω load at full output swing, and what is the resulting voltage compliance?

Yes, the THS4031IDG4 can drive a 150Ω load with ±12.9V output swing at ±15V supply (±12V min), delivering up to 86mA per polarity. At ±5V supply, it delivers ±3.5V into 150Ω (±3V min), supporting 23mA. Output compliance remains linear across this range, with <0.02% differential gain error-critical for video and imaging applications where amplitude fidelity directly impacts image quality in systems using THS4031IDG4.