Texas Instruments TPS3813I50QDBVRQ1

Overview

TPS3813I50QDBVRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive supervisory IC with window-watchdog functionality, precision 4.55 V supply-voltage monitoring (VIT), 25 ms power-on reset delay, and open-drain RESET output - used to ensure safe startup and runtime supervision of ADAS domain controllers and digital cockpit processors.

For engineers reviewing the TPS3813I50QDBVRQ1 datasheet, TPS3813I50QDBVRQ1 pinout, TPS3813I50QDBVRQ1 application, or TPS3813I50QDBVRQ1 equivalent, key selection criteria include its programmable watchdog window ratio (1:127.7 max), −40°C to +125°C operating range, 9 μA typical supply current, and SOT-23-6 package compatibility with space-constrained automotive PCBs.

Technical Context

The TPS3813I50QDBVRQ1 integrates a bandgap-referenced voltage comparator for precise 4.55 V threshold detection with 60 mV hysteresis (VHYS), plus a dual-stage oscillator-based window-watchdog circuit that enforces both upper timeout (e.g., 2.5 s when WDT = VDD) and lower boundary (e.g., 19.6 ms when WDR = VDD) timing constraints on WDI pulses.

Its functional block includes rising-edge detection on WDI, configurable WDT/WDR input logic for ratio selection, reset timer with 25 ms fixed delay after VDD crosses VIT, and open-drain output stage capable of sinking 5 mA - all operating from 2 V to 6 V supply without external components.

Key Specifications

Pinout & Package

TPS3813I50QDBVRQ1 is housed in a 6-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, optimized for high-density automotive PCB layouts with thermal resistance R_θJA = 202.9°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3813I50QDBVRQ1, the TPS3813K33QDBVRQ1 offers identical watchdog flexibility but targets 3.3 V rails, while the MAX6373KA29+T provides basic reset and watchdog functions without windowed timing - making it unsuitable for ASIL-B/C safety requirements.

Availability

TPS3813I50QDBVRQ1 is available at Aetrix Electronics and suitable for ADAS domain controllers, digital cockpit processing units, and automotive telematics control units requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TPS3813I50QDBVRQ1 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 automotive-grade ICs with deep expertise in functional safety and reliability engineering.

The TPS3813-Q1 product line was designed specifically for ISO 26262-compliant automotive systems, providing hardware-enforced supervision to meet ASIL-B requirements in safety-critical ECUs.

FAQ

What is the exact supply-voltage threshold (VIT) of the TPS3813I50QDBVRQ1?

The TPS3813I50QDBVRQ1 has a nominal supply-voltage threshold of 4.55 V, with a guaranteed range of 4.45 V to 4.65 V across −40°C to +125°C. This value is factory-trimmed and specified in Section 6.5 of the datasheet. The device uses this threshold to assert RESET whenever VDD falls below it, ensuring reliable supervision of 5 V rails in automotive environments.

Does the TPS3813I50QDBVRQ1 support programmable watchdog timeout using an external capacitor?

Yes, the TPS3813I50QDBVRQ1 supports programmable upper watchdog timeout via an external capacitor connected between the WDT pin and GND. Capacitor values from 155 pF to 63 nF yield corresponding timeouts calculated as t_window,typ = (C_ext / 15.55 pF + 1) × 6.25 ms. This allows fine-grained tuning beyond the two fixed options (0.25 s and 2.5 s) provided by WDT pin strapping.

How does the window-watchdog function differ from a standard watchdog in the TPS3813I50QDBVRQ1?

Unlike standard watchdogs that only detect missed service pulses, the TPS3813I50QDBVRQ1 implements a true window-watchdog: it enforces both an upper timeout (e.g., 2.5 s) and a lower boundary (e.g., 19.6 ms when WDR = VDD). This prevents unsafe conditions caused by overly frequent or erratic WDI pulses - a critical requirement for ASIL-B software supervision in automotive ECUs.

What is the recommended bypass capacitor for the VDD pin of the TPS3813I50QDBVRQ1?

A 0.1 µF ceramic capacitor placed as close as possible to the VDD and GND pins is explicitly recommended in the datasheet (Section 7.3.1) to ensure stable operation during power-up and to suppress high-frequency noise. This capacitor maintains sufficient charge for internal circuitry during transient events and improves glitch immunity - especially critical in automotive power systems with switching regulators and load dumps.

Can the TPS3813I50QDBVRQ1 be used in non-automotive applications?

While the TPS3813I50QDBVRQ1 is AEC-Q100 qualified and optimized for automotive use, its electrical specifications - including −40°C to +125°C operation, 9 μA supply current, and 4.55 V threshold - make it technically suitable for industrial or harsh-environment applications requiring high-reliability supervision. However, its qualification documentation and failure-in-time (FIT) data are automotive-focused, so end-equipment certification remains the designer's responsibility.