Texas Instruments TDC1000QPWRQ1

Overview

TDC1000QPWRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive-qualified ultrasonic sensing analog front-end (AFE) for time-of-flight (TOF) measurement in level, flow, concentration, and proximity applications. It integrates dual TX/RX channels, programmable excitation (31.25 kHz–4 MHz), low-noise amplification with 50 psRMS STOP jitter, and RTD-based temperature sensing with 0.02°CRMS matching accuracy.

For engineers reviewing the TDC1000QPWRQ1 datasheet, TDC1000QPWRQ1 pinout, TDC1000QPWRQ1 application, or TDC1000QPWRQ1 equivalent, this device supports SPI-configurable ultrasonic transducer interfacing, differential TOF measurement via automatic channel swapping, low-power operation (1.8 µA at 2 SPS), and direct integration with external TDCs or MCUs for picosecond-resolution timing.

Technical Context

The TDC1000QPWRQ1 implements a fully configurable analog signal chain: its transmitter supports up to 31 pulses with programmable frequency division (CLKIN/2^{TX_FREQ_DIV+1}) and optional pulse damping; its receiver features cascaded LNA (20 dB gain, 2 nV/√Hz input noise) and PGA (0–21 dB, 3 dB steps) with external filter access and dual comparators for echo qualification and zero-crossing detection.

It operates in three defined modes (Mode 0/1/2) optimized for tank-level, flow metering, or proximity sensing, with START/STOP pulse generation synchronized to TRIGGER input and compatible with external TDC7200 or MCU-based timing capture. Temperature sensing uses two PT1000/500 RTD interfaces with RREF reference and 0.5°C absolute accuracy over –15°C to +85°C.

Key Specifications

Pinout & Package

TDC1000QPWRQ1 is housed in a 28-pin TSSOP package (9.70 mm × 4.40 mm), thermally rated at R_θJA = 83.5°C/W, and requires 100-nF bypass capacitors on all VDD pins per TI layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultrasonic AFE applications.

Compared with TDC1000QPWRQ1, TDC1000PWR offers identical functionality without automotive qualification, while TDC1010QPWRQ1 replaces external timing dependency with on-chip TDC at the cost of RTD capability and higher active current - making TDC1000QPWRQ1 optimal for temperature-critical, AEC-Q100-compliant ultrasonic sensing.

Availability

TDC1000QPWRQ1 is available at Aetrix Electronics and suitable for automotive fluid level instrumentation, industrial flow metering, and battery-powered proximity sensing requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for TDC1000QPWRQ1 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, embedded processing, and sensing technologies, with leadership in precision analog front-ends and automotive-qualified ICs.

The TDC1000QPWRQ1 belongs to TI's ultrasonic sensing AFE product line, designed specifically to enable high-accuracy, low-power time-of-flight measurement in automotive, industrial, and consumer fluid and proximity sensing systems.

FAQ

What is the primary function of the TDC1000QPWRQ1 in an ultrasonic sensing system?

The TDC1000QPWRQ1 serves as the analog front-end that conditions ultrasonic transducer signals - generating programmable transmit pulses, amplifying and filtering weak echoes with low-noise LNA/PGA stages, qualifying echoes via threshold/zero-crossing comparators, and outputting precise START/STOP timing pulses for external time-to-digital conversion. Its role is to convert raw acoustic events into deterministic digital timing references for TOF calculation in the TDC1000QPWRQ1-based system.

Does the TDC1000QPWRQ1 include an integrated time-to-digital converter (TDC)?

No, the TDC1000QPWRQ1 does not contain an integrated TDC. It generates START and STOP pulses with 50 psRMS jitter and relies on an external TDC (e.g., TI's TDC7200) or a high-resolution MCU timer to measure the time interval between them. This architecture separates analog conditioning from digital timing, allowing system-level optimization of resolution, power, and cost - a core design choice reflected in the TDC1000QPWRQ1 functional block diagram and timing specifications.

How does the TDC1000QPWRQ1 support temperature compensation in ultrasonic measurements?

The TDC1000QPWRQ1 supports temperature compensation by integrating a dual-channel RTD interface for PT1000 or PT500 sensors, with dedicated RTD1, RTD2, and RREF pins. It achieves 0.02°CRMS matching between channels and 0.5°C absolute accuracy (–15°C to +85°C), enabling real-time correction of sound velocity drift due to fluid or ambient temperature changes - a critical capability for accurate level, flow, and concentration calculations in the TDC1000QPWRQ1 system.

Can the TDC1000QPWRQ1 operate with both single and dual ultrasonic transducers?

Yes, the TDC1000QPWRQ1 supports both configurations: TX1/TX2 can drive one or two transducers independently, and RX1/RX2 accept echoes from either. Its automatic channel swapping feature enables true differential TOF measurement using two transducers - rejecting common-mode noise and improving zero-flow stability - while single-transducer setups use RX1 or RX2 selectively. This flexibility is explicitly documented in the TDC1000QPWRQ1 features list and functional description.

What SPI interface requirements does the TDC1000QPWRQ1 specify for configuration?

The TDC1000QPWRQ1 specifies a 4-wire SPI interface (CSB, SCLK, SDI, SDO) supporting up to 26 MHz clock frequency, with setup/hold times as low as 10–12 ns and SDO valid delay of 16 ns. It uses standard SPI mode 0 (CPOL = 0, CPHA = 0) and requires proper sequencing for register writes - particularly for CONFIG_0 and TOF_1 - to configure TX frequency division, pulse count, LNA feedback mode, and gain settings. These timing and protocol details are fully specified in Section 6.6 and 6.7 of the TDC1000QPWRQ1 datasheet.