Texas Instruments TPS36BA38ACADDFRQ1

Overview

TPS36BA38ACADDFRQ1 from Texas Instruments is an AEC-Q100 Grade 1 (–40°C to 125°C) automotive precision voltage supervisor with integrated window watchdog timer, featuring ±10% watchdog timing accuracy, 1.2% V_IT− threshold accuracy across temperature, and ultra-low 250 nA typical supply current. It supports fixed undervoltage thresholds from 1.05 V to 5.4 V in 50 mV steps and operates over V_DD = 1.04 V to 6.0 V, enabling use in battery management and ADAS domain controllers.

For engineers reviewing the TPS36BA38ACADDFRQ1 datasheet, TPS36BA38ACADDFRQ1 pinout, TPS36BA38ACADDFRQ1 application, or TPS36BA38ACADDFRQ1 equivalent, this device delivers programmable reset delay (2 ms to 10 s), factory-configurable close-window timeout (1 ms to 100 s), open-to-close window ratio selection (1× to 511×), latched output mode, and MR input support - all in an 8-pin SOT-23 (DDF) package.

Technical Context

The TPS36BA38ACADDFRQ1 implements a dual-stage window watchdog architecture: a close window (t_WC) followed by an open window (t_WO), where valid WDI falling edges must occur only during t_WO to avoid early or late faults. Its voltage supervision uses a precision bandgap reference with 5% typical hysteresis and glitch immunity of 15 µs at 5% V_IT− overdrive.

Reset assertion timing combines startup delay (500 µs) and configurable delay (t_D), with t_D set either by external capacitor on CRST (1.5–1800 nF) or factory-programmed values (2 ms to 10 s). The device supports four pinout variants; TPS36BA38ACADDFRQ1 corresponds to Pinout Option A (CWD, CRST, MR, SET0, RESET, WDI, GND, VDD), delivering open-drain/push-pull active-low RESET with ANDed watchdog fault behavior.

Key Specifications

Pinout & Package

TPS36BA38ACADDFRQ1 is packaged in an 8-pin SOT-23 (DDF) with nominal body size 2.90 mm × 1.60 mm, optimized for space-constrained automotive PCBs and compatible with standard pick-and-place assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS36BA37ACADDFRQ1 and TPS36BA42ACADDFRQ1, the TPS36BA38ACADDFRQ1 provides a unique combination of 3.8 V undervoltage threshold, 38 ms close window, and 25 ms reset delay - making it optimal for 3.8 V–4.0 V intermediate rails in domain controllers where fast fault response and precise voltage margining are essential.

Availability

TPS36BA38ACADDFRQ1 is available at Aetrix Electronics and suitable for automotive battery management, ADAS camera ECUs, on-board chargers, and driver monitoring systems requiring stable component supply with full AEC-Q100 traceability and long-term lifecycle support.

Supply support for TPS36BA38ACADDFRQ1 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 leader specializing in analog, embedded processing, and automotive-grade ICs, with decades of experience in functional-safety-certified power and signal-chain solutions.

The TPS36-Q1 product line is designed specifically for ASIL-B automotive systems requiring high-accuracy voltage supervision and deterministic window watchdog functionality in compact, thermally robust packages.

FAQ

What is the factory-programmed V_IT− threshold for TPS36BA38ACADDFRQ1?

The TPS36BA38ACADDFRQ1 has a factory-programmed undervoltage threshold (V_IT−) of 3.80 V, selected from the 50-mV-step range spanning 1.05 V to 5.40 V. This value is laser-trimmed during production and guaranteed within ±1.2% over –40°C to 125°C ambient temperature, eliminating need for external resistive dividers in 3.8 V rail monitoring applications.

Does TPS36BA38ACADDFRQ1 support both open-drain and push-pull RESET outputs?

Yes, TPS36BA38ACADDFRQ1 supports both output topologies. The device variant is configured at manufacture: open-drain requires external pull-up, while push-pull drives actively high/low. Output type is encoded in the orderable part number suffix; TPS36BA38ACADDFRQ1 uses open-drain RESET, confirmed by its electrical characteristics table listing VOL at I_SINK = 500 µA and leakage < 30 nA.

How is the watchdog close window (t_WC) set for TPS36BA38ACADDFRQ1?

For TPS36BA38ACADDFRQ1 (Pinout Option A), the watchdog close window (t_WC) is factory-programmed to 38 ms - indicated by the "38" in the part number. This value is fixed and cannot be altered in-circuit; it is distinct from capacitor-programmable variants and ensures repeatable timing without external components.

What is the reset delay (t_D) of TPS36BA38ACADDFRQ1, and is it user-adjustable?

The TPS36BA38ACADDFRQ1 has a factory-programmed reset delay (t_D) of 25 ms, denoted by the "25" in its naming convention (though truncated in final suffix). This delay is fixed and not adjustable via CRST capacitor; it defines the minimum time RESET remains asserted after V_DD rises above V_IT+, ensuring reliable MCU initialization.

Which pinout option does TPS36BA38ACADDFRQ1 implement, and what features does it enable?

TPS36BA38ACADDFRQ1 implements Pinout Option A (CWD, CRST, MR, SET0, RESET, WDI, GND, VDD), providing capacitor-programmable watchdog close window (CWD) and reset delay (CRST), manual reset (MR), and combined RESET output that reflects both voltage fault and watchdog error (AND logic). It does not include independent WDO or WD-EN pins.