Texas Instruments THS4140CDGK

Overview

THS4140CDGK from Texas Instruments is a high-speed fully differential amplifier designed for precision signal conditioning in ADC driver, antialiasing, and differential transmitter/receiver applications. It delivers 160 MHz –3 dB bandwidth (±15 V), 450 V/µs slew rate, –79 dB third-harmonic distortion at 1 MHz, 6.5 nV/√Hz input noise, and features shutdown mode with 0.88 mA quiescent current.

For engineers reviewing the THS4140CDGK datasheet, THS4140CDGK pinout, THS4140CDGK application, or THS4140CDGK equivalent, this device is selected for high-fidelity differential I/O where common-mode noise rejection, low distortion, wide supply range (±2.5 V to ±15 V), and power-down capability are critical in data acquisition and communications systems.

Technical Context

The THS4140CDGK implements a true fully differential signal path-differential input to differential output-enabling balanced output rejection of common-mode noise and reduction of second-harmonic distortion. Its BiComI bipolar process ensures high slew rate and low input-referred noise.

It supports single-ended-to-differential conversion via VOCM control, offers programmable output common-mode level, and integrates an active-low shutdown pin (PD) that places outputs in high-impedance state with >1 MΩ output impedance while drawing only 0.88 mA ICC(SD).

Key Specifications

Pinout & Package

THS4140CDGK is housed in an 8-pin MSOP PowerPAD™ package (DGK−8), featuring an exposed thermal pad on the underside for enhanced heat dissipation. The PowerPAD must be soldered to a thermally conductive PCB plane per TI SLMA002/SLMA004 guidelines to maintain junction temperature ≤125°C under load.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fully differential amplifier applications.

Compared with THS4141CDGK and THS4131CDGK, the THS4140CDGK uniquely provides active-low shutdown control in an 8-pin MSOP PowerPAD package-making it the only option among these three for power-aware, space-constrained differential ADC driver designs requiring dynamic power management.

Availability

THS4140CDGK is available at Aetrix Electronics and suitable for high-speed data acquisition, industrial communications interfaces, medical imaging front-ends, and RF IF signal conditioning requiring stable component supply and long-term production continuity.

Supply support for THS4140CDGK 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The THS414x family was engineered specifically for high-fidelity differential signal conditioning-targeting ADC drivers, antialiasing filters, and differential transceivers where distortion, noise, and common-mode rejection are design-critical.

FAQ

What is the function of the PD pin on the THS4140CDGK?

The PD (Power-Down) pin on the THS4140CDGK is an active-low control input that places the amplifier in low-power shutdown mode when pulled below ≈1.4 V above VCC−. In shutdown, THS4140CDGK draws only 0.88 mA and its outputs enter a high-impedance state (>1 MΩ), enabling dynamic power management in multi-channel systems without disrupting signal routing.

How does the VOCM pin affect THS4140CDGK performance in ADC driver applications?

The VOCM pin on THS4140CDGK sets the common-mode DC level of both differential outputs. When interfacing with an ADC that provides a reference voltage (e.g., VREF), connecting VOCM directly to VREF (with 0.1 µF bypass) aligns the THS4140CDGK output swing precisely to the ADC's input range-maximizing dynamic range and eliminating level-shifting errors. This direct coupling is a key advantage of THS4140CDGK in precision data acquisition.

Can THS4140CDGK operate from a single 5-V supply?

Yes, THS4140CDGK supports single-supply operation from 5 V to 30 V. With VCC+ = 5 V and VCC− = GND, VOCM defaults to mid-rail (2.5 V), enabling rail-to-rail-compatible differential output swing. Input common-mode range extends from –4 V to +4.5 V, allowing ground-referenced or biased single-ended inputs-making THS4140CDGK viable for cost-sensitive, low-voltage embedded systems.

Why is resistor matching critical when using THS4140CDGK in closed-loop configurations?

Resistor matching directly impacts THS4140CDGK's CMRR, PSRR, and second-harmonic cancellation. Mismatched feedback or gain resistors unbalance the differential path, degrading common-mode rejection and increasing even-order distortion. TI recommends ≤1% tolerance resistors (or better) for Rf and Rg networks to preserve the THS4140CDGK's specified 84 dB CMRR and –79 dB THD performance in production designs.

What thermal considerations apply to the THS4140CDGK DGK package?

The THS4140CDGK uses a thermally enhanced MSOP PowerPAD™ (DGK−8) package with an exposed die paddle. To prevent junction temperature exceedance (>125°C), the thermal pad must be soldered to a dedicated copper pour connected to internal/external ground planes via multiple thermal vias. Per TI SLMA002, failure to implement this thermal path limits safe continuous power dissipation to just 385 mW at 25°C ambient-insufficient for sustained 160 MHz operation at full output swing.