Texas Instruments TPS3851H25EQDRBRQ1

Overview

TPS3851H25EQDRBRQ1 from Texas Instruments is a high-accuracy AEC-Q100 Grade 1 voltage supervisor with integrated programmable watchdog timer, featuring 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 automotive ADAS domain controllers requiring functional safety compliance.

For engineers reviewing the TPS3851H25EQDRBRQ1 datasheet, TPS3851H25EQDRBRQ1 pinout, TPS3851H25EQDRBRQ1 application, or TPS3851H25EQDRBRQ1 equivalent, this device delivers precision undervoltage detection with hysteresis, user-selectable watchdog timing via CWD capacitor or factory presets, manual reset input, and wettable-flank VSON packaging for automated optical inspection in automotive production.

Technical Context

The TPS3851H25EQDRBRQ1 implements a precision bandgap-based comparator for VITN detection with 0.5% hysteresis and ±15% reset delay accuracy. Its watchdog logic uses a constant-current (375 nA) charge circuit on the CWD pin to determine timeout-either via external capacitor (0.1–1000 nF) or factory-programmed values (170–1840 ms).

It operates across 1.6 V–6.5 V supply range with 10 µA typical quiescent current, supports dual watchdog modes (enabled/disabled via SET1), and features independent WDO assertion during fault conditions while RESET remains deasserted-enabling granular fault diagnostics without full system reset.

Key Specifications

Pinout & Package

TPS3851H25EQDRBRQ1 is housed in a 3.00 mm × 3.00 mm, 8-pin VSON package with wettable flanks for solder-joint 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 and watchdog applications.

Compared with TPS3851H25EQDRBRQ1, the TPS3851H33EQDRBRQ1 offers identical functionality but with a fixed 3.3 V threshold, while TLV809E25DBVRQ1 reduces feature set and accuracy to meet simpler reset-only requirements in smaller footprint - neither is pin-compatible nor functionally interchangeable without schematic revision.

Availability

TPS3851H25EQDRBRQ1 is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, surround-view ECUs, front camera modules, and vehicle occupant detection sensors requiring stable component supply across extended temperature and long product lifecycles.

Supply support for TPS3851H25EQDRBRQ1 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 delivering analog and embedded processing solutions, with leadership in automotive, industrial, and power management ICs.

TPS3851H25EQDRBRQ1 belongs to TI's automotive-grade voltage supervisor product line, designed specifically for functional safety-critical power monitoring in ADAS, body electronics, and infotainment systems operating from –40°C to +125°C.

FAQ

What is the undervoltage threshold voltage for TPS3851H25EQDRBRQ1?

The TPS3851H25EQDRBRQ1 has a factory-programmed undervoltage threshold of 2.5 V (VITN = 2.5 V), with ±0.8% accuracy across –40°C to +125°C. This corresponds to a nominal trip point of 2.5 V, entering reset when VDD falls below 2.48 V and exiting reset (with hysteresis) at 2.5125 V. The H25 suffix explicitly denotes the 2.5 V version within the TPS3851-Q1 family.

Does TPS3851H25EQDRBRQ1 support both standard and extended watchdog timing modes?

Yes, TPS3851H25EQDRBRQ1 supports both standard and extended watchdog timing. Standard timing yields 170–230 ms (SET1 = 1, CWD pulled up) or 1360–1840 ms (SET1 = 1, CWD unconnected). Extended timing is selected via part number suffix (E-Q1), but the H25EQDRBRQ1 variant supports both ranges depending on CWD/SET1 configuration - confirmed in Section 7.1.1.1 of the datasheet.

How is the watchdog timer disabled on TPS3851H25EQDRBRQ1?

The watchdog timer on TPS3851H25EQDRBRQ1 is disabled by grounding the SET1 pin. When SET1 = 0 (VSET1 < 0.25 V), the watchdog is fully disabled and WDI is ignored. In this state, WDI must still be driven to VDD or GND to prevent increased supply current. Disabling occurs dynamically with a 150 µs setup time before watchdog re-enables.

What package type and dimensions does TPS3851H25EQDRBRQ1 use?

TPS3851H25EQDRBRQ1 uses an 8-pin VSON (DRB) package measuring 3.00 mm × 3.00 mm with wettable flanks. The thermal pad is internally connected to GND and must be soldered to a PCB ground plane. This package is optimized for automotive surface-mount assembly and automated optical inspection (AOI) of solder joints.

Is TPS3851H25EQDRBRQ1 qualified for automotive applications?

Yes, TPS3851H25EQDRBRQ1 is AEC-Q100 qualified for Grade 1 (–40°C to +125°C ambient), with HBM ±4 kV and CDM ±1 kV ESD ratings. It also includes functional safety documentation (FIT, FMEA, diagnostic coverage) to support ISO 26262 ASIL-B system development - making it suitable for ADAS, body control, and powertrain applications.