Texas Instruments TPS3851H25SQDRBRQ1

Overview

TPS3851H25SQDRBRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive voltage supervisor IC with integrated programmable watchdog timer, 0.8% undervoltage threshold accuracy (–40°C to +125°C), 200 ms reset timeout (±15%), and open-drain RESET/WDO outputs. It monitors supply rails from 1.8 V to 5.0 V and supports manual reset (MR) and watchdog disable (SET1) in a wettable-flank 3 mm × 3 mm VSON-8 package.

For engineers reviewing the TPS3851H25SQDRBRQ1 datasheet, TPS3851H25SQDRBRQ1 pinout, TPS3851H25SQDRBRQ1 application, or TPS3851H25SQDRBRQ1 equivalent, this page delivers verified functional safety-capable supervision parameters, factory-programmed vs. capacitor-based watchdog timing options, precision hysteresis (0.5%), and automotive-grade thermal performance (R_θJA = 47.7°C/W) for ADAS and ECU power integrity design.

Technical Context

The TPS3851H25SQDRBRQ1 implements a high-precision comparator-based undervoltage detection path with 0.5% hysteresis and 15% accurate reset delay timing, enabling robust startup and brownout recovery in tight-tolerance automotive systems. Its dual-output architecture separates system reset (RESET) from fault diagnostics (WDO), allowing independent handling of critical resets versus non-critical watchdog events.

Watchdog functionality operates via three configuration modes: factory-programmed standard (1.6 s typ) or extended (170 ms typ) timeouts selected by CWD/SET1 logic states, or user-adjustable timing using an external capacitor (0.1–1000 nF) charged by a 375 nA current source. The device disables watchdog response during RESET assertion and enforces 150 µs setup time when re-enabling.

Key Specifications

Pinout & Package

TPS3851H25SQDRBRQ1 uses a 3.00 mm × 3.00 mm, 8-pin VSON package with wettable flanks for automated optical inspection. Thermal pad is internally connected to GND and must be soldered to a large-area ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3851G25SQDRBRQ1, the TPS3851H25SQDRBRQ1 offers enhanced statistical accuracy assurance for functional safety audits, while MAX6373KA25+T provides basic reset capability at lower cost but without AEC-Q100 qualification or watchdog functionality.

Availability

TPS3851H25SQDRBRQ1 is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, surround-view ECUs, front camera modules, and vehicle occupant detection systems requiring stable component supply across extended product lifecycles.

Supply support for TPS3851H25SQDRBRQ1 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 TPS3851-Q1 product line delivers AEC-Q100 qualified voltage supervisors with integrated watchdog timers specifically engineered for functional safety-critical automotive electronics including ADAS, body control, and powertrain domains.

FAQ

What is the undervoltage threshold voltage for TPS3851H25SQDRBRQ1?

The TPS3851H25SQDRBRQ1 has a factory-programmed undervoltage threshold (V_ITN) of 2.5 V with ±0.8% accuracy over –40°C to +125°C. This value is laser-trimmed during production and applies to all units in the H-grade accuracy bin. The device also provides 0.5% hysteresis to prevent chatter near the threshold, making it suitable for monitoring 2.5 V rails in automotive microcontrollers and sensors.

How does the watchdog timeout work on TPS3851H25SQDRBRQ1?

The TPS3851H25SQDRBRQ1 supports two watchdog timeout modes: factory-programmed (170 ms or 1.6 s typical) selected via CWD/SET1 logic states, or user-adjustable using an external capacitor (0.1–1000 nF) on the CWD pin. A 375 nA internal current source charges the capacitor to 1.21 V to determine timeout. The watchdog is disabled when SET1 is grounded, and WDI is ignored during RESET assertion.

Is TPS3851H25SQDRBRQ1 qualified for automotive applications?

Yes, TPS3851H25SQDRBRQ1 is AEC-Q100 Grade 1 qualified with device temperature range –40°C to +125°C ambient, HBM ESD level 2 (±4 kV), and CDM level C4B (±1 kV). It is designed for automotive safety-critical systems and includes functional safety documentation to support ISO 26262 ASIL-B development. The wettable flank VSON-8 package further ensures manufacturability in automotive production lines.

What are the key differences between TPS3851H25SQDRBRQ1 and TPS3851G25SQDRBRQ1?

Both share identical pinout, package, and core functionality. TPS3851H25SQDRBRQ1 is binned to tighter statistical accuracy specifications (H-grade), providing enhanced confidence in V_ITN and hysteresis performance across temperature for functional safety validation. TPS3851G25SQDRBRQ1 meets standard G-grade specs. The H-grade part includes additional SPC data and test coverage required for ASIL-B system certification.

Can TPS3851H25SQDRBRQ1 monitor multiple voltage rails simultaneously?

No, TPS3851H25SQDRBRQ1 monitors only the VDD supply rail it is powered from. It does not include multiple independent input channels. To supervise multiple rails (e.g., 1.8 V, 3.3 V, 5.0 V), separate TPS3851H25SQDRBRQ1 devices or multi-rail supervisors like TPS389x-Q1 must be used. Each instance requires its own VDD connection, pullup resistors on RESET/WDO, and appropriate bypass capacitors.