Texas Instruments TPS3850G18QDRCRQ1

Overview

TPS3850G18QDRCRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive-qualified precision voltage supervisor with integrated programmable window watchdog timer. It monitors supply rails from 0.9 V to 5.0 V with ±0.8% threshold accuracy over –40°C to +125°C, delivers 10 µA typical supply current, and features factory-programmed or capacitor-adjustable reset (703 µs–3.22 s) and watchdog timeouts. It serves as a safety-critical power-rail monitor and fault-detection enabler in ADAS domain controllers.

For engineers reviewing the TPS3850G18QDRCRQ1 datasheet, TPS3850G18QDRCRQ1 pinout, TPS3850G18QDRCRQ1 application, or TPS3850G18QDRCRQ1 equivalent, this page provides verified functional context, validated pin roles, confirmed timing parameters for reset and window watchdog boundaries, and real-world automotive use cases requiring ISO 26262-aware supervision.

Technical Context

The TPS3850G18QDRCRQ1 implements a dual-comparator window architecture on the SENSE pin with independent overvoltage (VIT+(OV)) and undervoltage (VIT–(UV)) thresholds, each trimmed to ±0.8% accuracy across temperature. Its internal state machine evaluates CRST and CWD pin configurations every time SENSE re-enters the valid window, enabling dynamic timeout selection.

It integrates a dedicated window watchdog with selectable lower/upper timing boundaries (e.g., tWDL = 1.48–2.22 ms / tWDU = 23.4–31.6 ms at SET0=0/SET1=1), where WDI edge timing must fall strictly between those boundaries to prevent WDO assertion. The open-drain RESET and WDO outputs require external pullups and operate independently-WDO only asserts when RESET is high.

Key Specifications

Pinout & Package

TPS3850G18QDRCRQ1 is housed in a 3.00 mm × 3.00 mm, 10-pin VSON package (DRC) with exposed thermal pad connected internally to GND. Wettable flanks enable reliable solder-joint inspection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervision and watchdog applications.

Compared with TPS3850G18QDRCRQ1, TPS3851G18QDRCRQ1 adds NMI for richer fault reporting but increases BOM count, while MAX6373KA29+T sacrifices window supervision, accuracy, and watchdog programmability for simplicity and legacy compatibility.

Availability

TPS3850G18QDRCRQ1 is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, digital cockpit processing units, and telematics control units requiring stable component supply with AEC-Q100 qualification and functional safety documentation support.

Supply support for TPS3850G18QDRCRQ1 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 deep expertise in automotive-grade power management and functional safety solutions.

The TPS3850-Q1 product line delivers precision voltage supervision and programmable window watchdog functionality specifically for ISO 26262-compliant automotive ECUs where deterministic fault detection and rail integrity assurance are mandatory.

FAQ

What is the operating temperature range for the TPS3850G18QDRCRQ1?

The TPS3850G18QDRCRQ1 is qualified per AEC-Q100 Grade 1 with an ambient operating temperature range of –40°C to +125°C. This rating applies to the full device functionality including voltage supervision accuracy, watchdog timing, and reset delay performance - verified across the entire range with no derating required.

Does the TPS3850G18QDRCRQ1 support monitoring of sub-1.0 V rails?

The TPS3850G18QDRCRQ1 is specified for monitoring rails from 0.9 V to 5.0 V. While its SENSE pin accepts inputs down to GND, the device's internal reference and comparator architecture are optimized for ≥0.9 V thresholds. For sub-0.9 V rails, TI recommends the TPS3850H01Q1 variant, which supports adjustable undervoltage monitoring down to 0.4 V.

How is watchdog disable implemented on the TPS3850G18QDRCRQ1?

Watchdog disable on the TPS3850G18QDRCRQ1 is achieved by setting SET0 = 1 and SET1 = 0. When disabled, the WDI input is ignored, and WDO remains in high-impedance state regardless of WDI activity. This configuration is explicitly defined in Section 6.6 of the datasheet and requires no external components.

What is the accuracy of the factory-programmed reset delay in the TPS3850G18QDRCRQ1?

The factory-programmed reset delay in the TPS3850G18QDRCRQ1 achieves ±9.5% accuracy over –40°C to +125°C. This specification applies only to the default delay settings selected via CRST pin configuration (e.g., NC or 10-kΩ pullup), not to capacitor-programmed delays, which depend on external component tolerances.

Can the TPS3850G18QDRCRQ1 be used without external pullup resistors on RESET and WDO?

No - RESET and WDO are open-drain outputs and require external pullup resistors (1 kΩ to 100 kΩ) to VDD or appropriate logic rail. Omitting pullups results in undefined output states and failure to assert reset or watchdog signals. The datasheet specifies VOL ≤ 0.4 V at 3 mA sink current, confirming active-low open-drain operation.