Texas Instruments TPS3850H09QDRCRQ1

Overview

TPS3850H09QDRCRQ1 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 and watchdog timeouts. It serves as a safety-critical system monitor in ADAS domain controllers and digital cockpit processors.

For engineers reviewing the TPS3850H09QDRCRQ1 datasheet, TPS3850H09QDRCRQ1 pinout, TPS3850H09QDRCRQ1 application, or TPS3850H09QDRCRQ1 equivalent, key selection considerations include its 4% / 7% fault window options, open-drain RESET/WDO outputs, wettable-flank VSON-10 package for optical inspection, and watchdog disable capability via SET pins during development.

Technical Context

The TPS3850H09QDRCRQ1 implements a dual-comparator window architecture with precision internal reference and trimmed resistor divider, enabling simultaneous overvoltage (VIT+(OV)) and undervoltage (VIT–(UV)) detection on the SENSE pin. Its hysteresis is fixed at 0.5%, eliminating external components for noise immunity in tight-tolerance systems.

Watchdog timing uses a precision clock-based state machine with three configurable window ratios (1/8, 3/4, 1/2) selected by SET0/SET1 logic inputs and CWD pin configuration (capacitor or pullup). The dedicated WDO output asserts only when RESET is high, enabling fault classification via timing resolution between tWDL and tWDU boundaries.

Key Specifications

Pinout & Package

TPS3850H09QDRCRQ1 is housed in a 3.00-mm × 3.00-mm, 10-pin VSON package with wettable flanks for automated optical inspection (AOI) compatibility and enhanced solder-joint reliability in automotive PCB assemblies.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3850H09QDRCRQ1, TPS3851H09QDRCRQ1 adds manual reset capability and improved accuracy but increases cost and complexity, while MAX6373HATA+T provides basic reset only in larger footprint-neither matches the integrated window watchdog and automotive-grade programmability of TPS3850H09QDRCRQ1.

Availability

TPS3850H09QDRCRQ1 is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, digital cockpit processing units, telematics control units, and on-board wireless chargers requiring stable component supply across extended temperature and long product lifecycles.

Supply support for TPS3850H09QDRCRQ1 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 IC design and functional safety compliance.

The TPS3850-Q1 product line delivers AEC-Q100 qualified voltage supervisors with integrated window watchdog timers, engineered specifically for safety-critical automotive subsystems including ADAS, digital cockpits, and vehicle connectivity modules.

FAQ

What is the voltage threshold accuracy of the TPS3850H09QDRCRQ1 over temperature?

The TPS3850H09QDRCRQ1 achieves ±0.8% maximum voltage threshold accuracy for both overvoltage (VIT+(OV)) and undervoltage (VIT–(UV)) detection across the full AEC-Q100 Grade 1 operating range of –40°C to +125°C. This specification is verified per TI's production test methodology and applies to the SENSE pin monitoring rails from 0.9 V to 5.0 V. The accuracy includes contributions from reference drift, resistor divider mismatch, and comparator offset - all characterized and binned during manufacturing. TPS3850H09QDRCRQ1 maintains this performance without external calibration components.

How does the watchdog disable function work on the TPS3850H09QDRCRQ1?

The TPS3850H09QDRCRQ1 watchdog can be disabled by setting both SET0 and SET1 pins high (≥0.8 × VDD). When disabled, the WDO output remains in high-impedance state regardless of WDI activity, and the watchdog timing circuit is powered down to reduce current consumption. Critically, WDI must not be left floating in this mode - it must be actively driven to either VDD or GND. This behavior is explicitly defined in Section 6.6 of the datasheet and validated across temperature. TPS3850H09QDRCRQ1 retains full reset supervision functionality even with watchdog disabled.

What package type and dimensions does the TPS3850H09QDRCRQ1 use?

The TPS3850H09QDRCRQ1 is packaged in a 3.00-mm × 3.00-mm, 10-pin VSON (DRC) package with exposed thermal pad and wettable flanks. The body size is precisely 3.00 mm × 3.00 mm with 0.5-mm lead pitch. Wettable flanks enable full-side optical inspection of solder fillets - a requirement for automotive zero-defect manufacturing. The thermal pad is internally connected to GND and must be soldered to a large-area ground plane per TI's layout guidelines. This package is distinct from larger alternatives like TDFN-14 or SOIC-8 used by non-automotive supervisors.

Can the TPS3850H09QDRCRQ1 monitor supply rails below 0.9 V?

No, the TPS3850H09QDRCRQ1 is factory-programmed for 0.9 V nominal SENSE threshold and supports monitoring rails from 0.9 V to 5.0 V only. Its internal resistor divider and reference architecture are optimized for this range; attempting to monitor sub-0.9 V rails results in degraded accuracy and undefined behavior outside datasheet specifications. For lower-voltage supervision (e.g., 0.4 V core rails), TI recommends the TPS3850H01QDRCRQ1 variant, which uses an external resistor divider and is explicitly characterized down to 0.4 V. TPS3850H09QDRCRQ1 does not support adjustable thresholds via external components.

What is the purpose of the CRST and CWD pins on the TPS3850H09QDRCRQ1?

The CRST pin programs the reset timeout period (tRST) using either a capacitor-to-GND (703 µs to 3.22 s range) or 10-kΩ pullup to VDD (factory-programmed options: 8.5–11.5 ms or 170–230 ms). The CWD pin similarly programs the watchdog upper boundary (tWDU) and lower boundary (tWDL) via capacitor or pullup. Both pins are evaluated by an internal state machine every time SENSE re-enters the valid window, with 381 µs initialization time (tINIT). These pins enable field-programmable timing without requiring different part numbers. TPS3850H09QDRCRQ1's CRST/CWD architecture eliminates need for external RC networks while maintaining precision through factory-trimmed charge currents.