Texas Instruments TUSS4470TRTJR

Overview

TUSS4470TRTJR from Texas Instruments is an integrated ultrasonic sensor IC combining transducer driver (H-bridge), logarithmic amplifier front-end, and SPI-configurable signal processing for industrial time-of-flight sensing. It delivers 86-dB input dynamic range, supports 40 kHz–1 MHz transducer frequencies, operates with 1.7 mA standby current, and provides analog echo envelope output (VOUT), zero-crossing detection (OUT3), and programmable threshold interrupt (OUT4). It enables high-accuracy liquid level measurement in tanks.

For engineers reviewing the TUSS4470TRTJR datasheet, TUSS4470TRTJR pinout, TUSS4470TRTJR application, or TUSS4470TRTJR equivalent, key selection considerations include its configurable H-bridge drive mode (direct or pre-driver), programmable bandpass filter (40–500 kHz), logarithmic gain scaling (25–46 mV/dB), low-power sleep mode (350 µA), and SPI-controlled burst timing - all critical for robust ultrasonic ranging in noisy industrial environments.

Technical Context

The TUSS4470TRTJR implements a dual-path excitation architecture: internal H-bridge drives transducers directly (up to 36 V on VDRV) or acts as pre-driver for external FETs, with configurable burst patterns via IO1/IO2 pins and SPI register control. Its receive path features a low-noise amplifier (gain selectable 10–20 V/V), digitally tunable bandpass filter (center frequency 40–500 kHz, Q = 3–5.2), and wideband logarithmic amplifier enabling 82–92 dB dynamic range.

Signal conditioning includes demodulated analog echo output (VOUT), zero-crossing comparator (OUT3), and programmable threshold interrupt (OUT4) with hysteresis (7–68 mV); all outputs are referenced to a regulated 3.3–5.5 V digital supply (VDD) while power stages accept 5–36 V (VPWR) and 5–21.4 V (VDRV).

Key Specifications

Pinout & Package

Package: 20-pin WQFN (RTJ), 4.00 mm × 4.00 mm, exposed thermal pad - optimized for compact PCB layout and thermal dissipation in sealed ultrasonic modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultrasonic transducer driver and receiver applications.

Compared with TUSS4470TRTJR, TUSS4460RTJR trades dynamic range and configurability for lower unit cost, while PGA460TPWR adds computational intelligence at the expense of external driver circuitry and development overhead - making TUSS4470TRTJR optimal for balanced performance, integration, and ease of implementation in industrial ranging.

Availability

TUSS4470TRTJR is available at Aetrix Electronics and suitable for industrial tank level sensing, automotive parking assist, material presence detection, and conveyor belt object counting requiring stable component supply and long-term manufacturability.

Supply support for TUSS4470TRTJR 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 precision signal chain and power management solutions.

The TUSS4470TRTJR belongs to TI's ultrasonic sensing portfolio, designed specifically for industrial and automotive time-of-flight applications requiring high dynamic range, low power, and flexible transducer interface - not general-purpose signal conditioning.

FAQ

What is the maximum transducer frequency supported by the TUSS4470TRTJR?

The TUSS4470TRTJR supports transducer frequencies from 40 kHz to 1 MHz in direct-drive mode, and up to 440 kHz in pre-driver mode. The actual usable upper limit depends on external clock accuracy applied to IO1/IO2 pins and transducer mechanical resonance - the device's configurable bandpass filter (40–500 kHz) and logarithmic amplifier ensure optimal signal integrity across this full range. TUSS4470TRTJR's architecture enables reliable operation at 1 MHz only when external clock jitter is minimized and transducer impedance matches the H-bridge output capability.

How does the TUSS4470TRTJR achieve 86-dB input dynamic range?

The TUSS4470TRTJR achieves 86-dB input dynamic range through a cascaded analog front end: a low-noise amplifier (LNA) with selectable gain (10–20 V/V), followed by a digitally tunable bandpass filter (40–500 kHz), and a wideband logarithmic amplifier that compresses large input swings into a linear VOUT scale (25–46 mV/dB). This architecture allows TUSS4470TRTJR to resolve microvolt-level echoes from distant targets while avoiding saturation from millivolt-level reflections off nearby objects - all within a single IC without external gain switching.

Can the TUSS4470TRTJR operate with a single transducer for both transmit and receive?

Yes, the TUSS4470TRTJR supports single-transducer operation using time-division multiplexing: the H-bridge drives the transducer during burst, then switches to high-impedance receive mode while the same transducer captures returning echoes on INP/INN. This is enabled by internal timing control and automatic isolation circuitry - no external transmit/receive (T/R) switch is required. TUSS4470TRTJR's dedicated SGND and differential input structure minimizes crosstalk, making it ideal for compact, low-cost ultrasonic modules where board space is constrained.

What is the purpose of the FLT pin on the TUSS4470TRTJR?

The FLT pin on the TUSS4470TRTJR connects to an external RC network (typically 6.25 kΩ resistor to ground and 15 nF capacitor) that sets the cutoff frequency of the internal low-pass filter following the logarithmic amplifier. This filter smooths the demodulated echo envelope on VOUT, reducing high-frequency noise before ADC sampling. The FLT network also influences log conformance error and pedestal voltage (VO_PDSTL), so component tolerance directly affects measurement repeatability - TUSS4470TRTJR's datasheet specifies 1% resistor and 5% capacitor tolerances for optimal performance.

Does the TUSS4470TRTJR require external components for H-bridge operation?

Yes, the TUSS4470TRTJR requires external components for robust H-bridge operation: a charge capacitor (typically 10–47 µF) on the VDRV pin to supply peak current during transducer excitation, reverse-current protection diode (D1) if VPWR varies widely, and series resistor (RPWR) to limit inrush current during power-up. In pre-driver mode, external high-current FETs and gate resistors are also needed. These components are mandatory per TI's layout guidelines - omitting them risks VDRV instability, spurious echoes, or permanent damage to TUSS4470TRTJR's internal MOSFETs.