Texas Instruments THS4509QRGTRQ1

Overview

THS4509QRGTRQ1 from Texas Instruments is a wideband, fully differential amplifier qualified for automotive applications, featuring 1.9 nV/√Hz input voltage noise, –75-dBc HD2 and –80-dBc HD3 at 100 MHz (2 Vpp, G = 10 dB), 1900 MHz small-signal bandwidth, and 6600 V/μs slew rate. It serves as a high-linearity ADC driver in 5-V data-acquisition systems requiring precise dc-coupled signal conditioning.

For engineers reviewing the THS4509QRGTRQ1 datasheet, THS4509QRGTRQ1 pinout, THS4509QRGTRQ1 application, or THS4509QRGTRQ1 equivalent, key selection criteria include output common-mode control accuracy (<5 mV offset), 2 ns 1% settling time for pulsed radar front-ends, power-down quiescent current (0.65 mA), and QFN-16 (RGT) thermal performance (RθJA = 50.8 °C/W).

Technical Context

The THS4509QRGTRQ1 employs a fully differential architecture with integrated output common-mode voltage control circuitry that maintains output CM within ±5 mV of the set point when CM input is between 1.25 V and 3.5 V. Its minimum stable gain is 2 V/V (6 dB), optimized for 10 dB operation in high-speed ADC interface designs.

It supports dual-supply operation from ±1.5 V to ±2.5 V (3 V to 5 V total), delivers 4.8 V differential output swing into 100 Ω loads at 5 V supply, and features 90 dB CMRR and 1.35 MΩ||1.77 pF differential input impedance - enabling robust single-ended-to-differential conversion with minimal distortion up to 1.5 GHz large-signal bandwidth.

Key Specifications

Pinout & Package

The THS4509QRGTRQ1 is housed in a 16-pin QFN package (RGT) with exposed thermal pad, optimized for low-inductance PCB layout and thermal dissipation in automotive under-hood environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with THS4521RGTT and LMH5401RTVT, the THS4509QRGTRQ1 uniquely balances automotive qualification, integrated output common-mode control, and 1900 MHz bandwidth at 37.7 mA quiescent current - making it the only option among the three qualified for AEC-Q100 Grade 1 radar signal chains requiring dc-coupled ADC interfacing.

Availability

THS4509QRGTRQ1 is available at Aetrix Electronics and suitable for adaptive cruise control, blind spot detection, and collision warning systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for THS4509QRGTRQ1 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 specializing in analog and embedded processing technologies, with leadership in high-performance signal chain solutions.

The THS4509QRGTRQ1 belongs to TI's automotive-qualified high-speed amplifier product line, designed specifically for demanding ADAS sensor signal conditioning where low noise, low distortion, and dc-coupled differential drive are critical.

FAQ

What is the minimum stable gain for the THS4509QRGTRQ1?

The THS4509QRGTRQ1 has a minimum stable gain of 2 V/V (6 dB). While it can operate stably at this gain, its AC performance-including bandwidth, distortion, and settling time-is optimized for 10 dB operation. At G = 10 dB, it achieves 1900 MHz small-signal bandwidth and –80-dBc HD3 at 100 MHz, making this gain setting preferred for most high-speed ADC driver applications.

Does the THS4509QRGTRQ1 support dc-coupled output to an ADC?

Yes, the THS4509QRGTRQ1 supports true dc-coupled output via its integrated output common-mode control circuit. When the CM pin is set to the ADC's reference midpoint (e.g., 2.5 V for a 5-V supply), the amplifier maintains output common-mode voltage within ±5 mV, enabling direct connection to mid-supply-referenced ADC inputs without external level-shifting components.

What is the power-down behavior of the THS4509QRGTRQ1?

When the PD pin is driven low (≤0.7 V + VS–), the THS4509QRGTRQ1 enters power-down mode with quiescent current reduced to 0.65 mA (typical). Turn-on delay is 55 ns, and turn-off delay is 10 μs. Input bias current drops to 100 µA, and input impedance becomes 50 kΩ||2 pF - preserving signal integrity during rapid wake/sleep transitions in automotive radar modules.

How does the THS4509QRGTRQ1 handle common-mode rejection?

The THS4509QRGTRQ1 provides 90 dB common-mode rejection ratio (CMRR) at DC and maintains >60 dB up to 100 MHz. This high CMRR, combined with its fully differential architecture and balanced 1.35 MΩ||1.77 pF input impedance, effectively suppresses engine noise, switching regulator ripple, and other board-level common-mode interference in automotive environments.

What thermal considerations apply to the THS4509QRGTRQ1 in automotive applications?

The THS4509QRGTRQ1 uses a thermally enhanced 16-pin QFN (RGT) package with an exposed pad. Its junction-to-ambient thermal resistance is 50.8 °C/W. For reliable operation at 125°C ambient, the thermal pad must be soldered to a solid copper ground plane with ≥4 thermal vias. Failure to implement proper thermal relief risks exceeding the 150°C maximum junction temperature, especially at full 37.7 mA quiescent current.