Texas Instruments TPS3850H18QDRCRQ1

Overview

TPS3850H18QDRCRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive-grade 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 open-drain RESET/WDO outputs. It is used in ADAS domain controllers to ensure microcontroller integrity during voltage transients and watchdog timeout events.

For engineers reviewing the TPS3850H18QDRCRQ1 datasheet, TPS3850H18QDRCRQ1 pinout, TPS3850H18QDRCRQ1 application, or TPS3850H18QDRCRQ1 equivalent, key selection criteria include its 0.5% hysteresis, factory-programmed or capacitor-adjustable reset/watchdog timing, 4%/7% fault window options, and VSON-10 wettable flank package for automotive solder-joint inspection.

Technical Context

The TPS3850H18QDRCRQ1 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 pins every time SENSE re-enters the valid window, enabling dynamic reconfiguration of reset and watchdog delays.

It supports three watchdog operating modes-enabled via SET0/SET1 logic inputs-with selectable window ratios (1/8, 3/4, 1/2) and upper/lower boundary timing ranging from 7.65 ms to 1.6 s. The WDO output asserts only when RESET is high, providing fault isolation between power and watchdog events.

Key Specifications

Pinout & Package

VSON-10 (3.00 mm × 3.00 mm) package with exposed thermal pad connected internally to GND; wettable flanks support AOI-compatible reflow and reliability validation in automotive production.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3850H18QDRCRQ1, TPS3851H18QDRCRQ1 adds NMI capability without layout change, while MAX6373HUT+T trades accuracy, programmability, and AEC-Q100 compliance for lower cost and smaller footprint in non-safety-critical roles.

Availability

TPS3850H18QDRCRQ1 is available at Aetrix Electronics and suitable for ADAS domain controllers, digital cockpit processing units, automotive telematics control units, on-board chargers, and driver monitoring systems requiring stable component supply across extended automotive lifecycles.

Supply support for TPS3850H18QDRCRQ1 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 automotive, industrial, and power management solutions.

The TPS3850-Q1 product line delivers AEC-Q100 qualified precision supervisors with integrated window watchdogs, designed specifically for safety-critical automotive ECUs where deterministic power and firmware monitoring is mandatory.

FAQ

What is the voltage threshold accuracy specification for TPS3850H18QDRCRQ1 over temperature?

The TPS3850H18QDRCRQ1 achieves ±0.8% maximum voltage threshold accuracy for both overvoltage (VIT+(OV)) and undervoltage (VIT–(UV)) detection across the full AEC-Q100 Grade 1 temperature range of –40°C to +125°C. This accuracy is measured on the SENSE pin and includes all process, voltage, and temperature variations - enabling reliable supervision of 1.8 V rails without derating or external calibration. The TPS3850H18QDRCRQ1 maintains this spec using factory-trimmed references and resistor dividers.

How does the watchdog disable feature work on TPS3850H18QDRCRQ1?

The TPS3850H18QDRCRQ1 watchdog can be disabled using the SET0 and SET1 logic inputs: setting SET0 = 1 and SET1 = 0 forces watchdog disable mode, regardless of CWD configuration. When disabled, the WDO output remains high-impedance and WDI input is ignored - eliminating spurious timeouts during bootloader execution or firmware updates. The TPS3850H18QDRCRQ1 requires WDI to be actively driven (not floating) in disabled mode, per datasheet Section 5.

What package type and dimensions does TPS3850H18QDRCRQ1 use?

The TPS3850H18QDRCRQ1 uses a 3.00 mm × 3.00 mm, 10-pin VSON package (orderable code DRC) with an exposed thermal pad connected internally to GND. Its wettable flanks enable automated optical inspection of solder fillets - a critical requirement for automotive PCB assembly per IATF 16949. The package has 0.5 mm pin pitch and is RoHS-compliant and lead-free.

Can TPS3850H18QDRCRQ1 monitor a 1.8 V rail with 4% or 7% fault window?

Yes - the TPS3850H18QDRCRQ1 supports both 4% and 7% fault window options for precision supervision of 1.8 V rails. With nominal VIT+(OV) = 1.872 V and VIT–(UV) = 1.728 V (for 4% window), or VIT+(OV) = 1.926 V and VIT–(UV) = 1.674 V (for 7% window), the device ensures reset is asserted before the 1.8 V rail exceeds SoC operational limits. These windows are fixed per device variant and confirmed in the TPS3850H18QDRCRQ1 datasheet Section 6.5.

What is the minimum and maximum reset delay achievable with TPS3850H18QDRCRQ1?

The TPS3850H18QDRCRQ1 supports reset delay (tRST) from 170 ms (factory-programmed, ±9.5% accuracy) up to 3.22 seconds (capacitor-programmed with 1000 nF on CRST). Minimum tRST is 703 µs using 0.1 nF on CRST. All capacitor-based delays follow Equation 3 in the datasheet and are validated across –40°C to +125°C. The TPS3850H18QDRCRQ1's CRST pin evaluation time (tINIT = 381 µs) ensures stable delay selection after each SENSE window re-entry.